This page: http://monitor.mikes.fi/ionclock/
Machines and IPs:
Strontium/linux .45.99 (strontium.ad.vtt.fi)
win .45.23 (ESPTE1M012-ioni.ad.vtt.fi)
kavi .45.190 (kavi.ad.vtt.fi)
News and notable results
2021-04-30: trapping again after IR-camera BBR-characterization. New machined alu C-beam mount
2021-01-25: first ions trapped after x-mas break. Intensifier+PCO needed for beam-alignment
2021-01-22: new mu-shields delivered. inner and mid-shields installed and fit ok
2020-12-03: Initial measurement of repumper-shift: -2600 (C1) to -2900 Hz (C4)
2020-11-18: New Ion page for clock-run data
2020-11-04: clock run with new HelRes (now 14.424 MHz) and new B-beam direction, but only 800us probe
2020-09-24: Move 2019 results to index_2019
2020-09-24: Secular frequencies with tickler + photon-correlation
2020-09-23: new 14.404 MHz Magic-RF Helical-Resonator
2020-07-02: Fourier limited 4 Hz linewidth with 180ms probe-pulse. Night, no metro.
2020-06-11: Second clock run, OD2 with 4ms probe, only C1, C2 peaks.
2020-05-17: D5/2 lifetime, random-telegraph method with 405nm and fit
2020-04-24: First clock run! 2.5ms probe, stability 2e-13/sqrt(tau_s)
2020-04-01: trapping single ion again, after 405 laser broke
2020-01-31: Move comb-plots to comb
2020-01-15: For temperatures, see DAQ
2019-12-19: Micromotion map, 3D pictures
2019-11-29: Cavity mode number, Comb mode number. Cavity absolute frequency.
2019-11-08: -C2 Zeeman component linewidth estimate of 800 Hz.
2019-11-05: Zeeman peaks with B-shield (1.6 uT estimate).
2019-11-04: Now with first B-shield. Laminated plywood + metglas.
2019-07-12: Zeeman peaks in ambient (66uT estimate) B-field. First clock-spectrum!
2019-07-10: Initial clock-transition search...
2019-07-10: Page created.
2019-06-18: ion photo and secular frequencies
Ion still in the trap!
Both RF-monitor and secular frequency show relative change of ca 0.00005/0.06025 = 8e-4, for the 1.8MHz axial frequency this is 1500 Hz.
Compare to oscilloscope resolution at 8-bit which is 1/256 = 4e-3.
Similar settings in late May gave 1.7898 MHz, now ca 1.7885 MHz. NOTE axial mode has lower frequency than normal because V12common = 0V.
Secular axial mode measurements from yesterday, RIDs 15041 - 15072, together with new RF-monitor measured with DMM
ca 14:00Z turn off lasers. turn off PMT. leave ion trapped.
RID 15042 - 15072: secular tickler, axial mode, C-beam
RID 15041: secular tickler, axial mode, C-beam.
RID15036: secular tickler, axial mode 1.781-1.79 MHz with A-beam
u-motions again A 15%, B 25%, C 28%
Fluorescence level changes very much when heating the B-fiber!
Optimize beam alignment A, B, C, ASE - but all were quite ok to begin with..
422 lock to Rb-line is quite unstable. unlocked twice while measuring u-motions etc.
umotions: A: 13% (7 s), B: 13% (15 s), C: 22% (8 s)
set 422-detuning to 208 MHz
11:44Z: Try to load: 1.6A, 1.59 W. Ion! at 11:52:40Z!
Compensation voltages: [-0.24511, +0.24511, -15.7661, +84.3065]
405: 3.3 mW.
ASE powers: 1092: 11.5 mW, 1033: 68 uW
Using ASI camera, no intensifier
Only inner magnetic shield is installed
422nm detuning: 185 MHz.
422nm on ion breadboard in A free-space beam ca 20uW. A-objective 1.5uW, B 2.5 uW, C 1.8 uW
461 power: 440 uW on ion breadboard. Check with Sr dispenser: 196.48 mA, 4.642 kOhm.
11:50Z Switch lasers off.
11:00Z Switch lasers on. No ion in the trap?
14:28Z turn off lasers. leave ion trapped
Detuning-scans at V12cm=0V:
NOTE 0.5*axial plotted, to get all datapoints close to eachother
Summary of results:
[-5.8 x 26.6721 x] V -> ( 958830, 1003244, 1975363) Hz
[-5.0 x 27.7201 x] V -> ( 982384, 1025684, 1950869) Hz
[-4.0 x 29.0301 x] V -> (1010912, 1053126, 1919859) Hz
[-3.0 x 30.3401 x] V -> (1038747, 1079756, 1888188) Hz
[-2.0 x 31.6501 x] V -> (1065803, 1105771, 1855910) Hz
[-1.0 x 32.9601 x] V -> (1092152, 1131241, 1823320) Hz
[ 0.0 x 34.2701 x] V -> (1117918, 1156046, 1789792) Hz
V12diff = 0.2451 V constant
V34diff = 50.0363 V constant
shift per volt = (+25800, +24800, -33500)
axial scan 1788-1792 kHz
rhi scan 1154-1158 kHz
rlo scan 1116-1120 kHz
uMotion A 2.6%, B 5.5%, C 7.2%
Set Vbias = [0 x 34.2701 x]
shift per volt = (+25500, -32600)
axial scan 1821-1825 kHz
rhi scan 1130-1134 kHz
uMotion A 3.4%, B 4.1%, C 7.1%
Set Vbias = [-1 x 32.9601 x]
shift per volt = (+2700, +26000, -32300)
axial scan 1854-1858 kHz
rhi scan 1104-1108 kHz
rlo scan 1064-1068 kHz
uMotion A 3.9%, B 2.4%, C 6.9%
Set Vbias = [-2 x 31.6591 x] V
shift per volt = (+27800, +26600, -31700)
axial scan 1887-1891 kHz
rhi scan 1078-1082 kHz
rlo scan 1037-1041 kHz
uMotion A 3.4%, B 3.2%, C 7.3%
Set Vbias = [-3.0 x 30.3401 x]
Observed shift per volt = (+28500, +27400, -31000) Hz
axial scan 1918-1922 kHz
rhi scan 1051-1055 kHz
rlo scan 1009-1013 kHz
uMotion A 4.4%, B 4.6%, C 7.6%
set Vbias = [-4 x 29.0301 x] (x not changed)
Observed shift per volt V12cm (x, y, z) = (+29200, +27700, -31300) Hz
axial scan 1947-1954 kHz
rhi scan 1023-1027 kHz - could use even more tickler than 7dB att
rlo scan 980-984 kHz
uMotion A 4.4%, B 5.1%, C 7%
rhi ca +2.7 kHz/0.1V, expect +22 kHz shift
axial ca -3 kHz/0.1V, so expect -24 kHz shift
Set new Vbias = [-5.0 0.2451, 27.7201, 50.0363]
(x, y, z) = (958830, 1003244, 1975363 Hz ) Yesterday: (959049, 1003521, 1975940)
fit fails - too wide scan?
Vbias = [-5.8 0.2451 26.6721 50.0363]
NOTE: figure P422 and P1092 not measured, just guesses. Program doesn't include window-transmission difference for A/B and C beams
uMotion 100kphot: A 4.7% in 13.9s, B 3.7% in 18.9s, C 7.5% in 13.8s
Fit uses -1 MHz correction, so 2*208 - 436 - 1 = -21 MHz (this agrees with the scanned points in the figure)
Is 208 MHz a good set-point for cooling?
ion appears maybe 20s after completed detuning-scan! (only points -23 MHz from 208MHz were scanned, no points in blue direction)
try detuning-scan to get cold ion?
no ion during first 60s with only A-beam, or during about 60s with ABC beams
detuning is 208 MHz
11:06Z turn on lasers.
synced with gitlab, new secular_prediction.py program
14:25Z lasers off. leave ion trapped
New version 'v2' of detuning-scan program with approximate lineshape fit.
TODO: automatically measure background-counts before or after the scan (or take this from blue-detuned data points?).
Add parameters for P422_A,B,C and P1092
uMotion A 6.1% in 10s, B 3.3% in 15.8s, C 4.3% in 10.5s
lasers on, ion still trapped
14:31Z turn off lasers. leave ion trapped.
Test how repeatable axial secular results are. RID14875 - RID14884 (10 repeats). each measurement ca 3 minutes.
(measurements via remote desktop, no activity in the lab)
f0 = [1975659, 1975684, 1975645, 1975599, 1975633, 1975598, 1975663, 1975607, 1975562, 1975502]
FWHM = [671, 559, 580, 610, 695, 628, 508, 630, 795, 657]
Standard deviation for resonance frequency ca 50Hz, for FWHM ca 75 Hz.
Systematic effects due to lab temperature change or helres-drift, cooling-laser intensity/polarization are probably (much) larger?
Trap parameter results:
Vbias -> [omega_secular x, y, z] (uMotion A, B, C)
[-5.8 0.2451 26.6721 50.0363] -> [ 959049 1003521 1975940] (7.7%, 1.2%, 2.8%)
[-5.9 0.2451 26.5411 50.0363] -> [ 956205 1000753 1978978] (7.1%, 1.6%, 2.5%)
[-6.0 0.2451 26.4101 50.0363] -> [ 953220 997869 1982072] (not measured)
[-6.0 0.2451 26.4101 50.0363] -> [ 952917 997615 1981450] (7.9%, 2.1%, 3.5%)
seculars at V12cm = -5.8 V
get uMotion A 7.7%, B 1.2%, C 2.8%
Go to Vbias = [-5.8 0.2451 26.6721 50.0363]
Seculars at V12cm = -5.9 V
get uMotion A 7.1%, B 1.6%, C 2.5%
Go to Vbias = [-5.9 0.2451 26.5411 50.0363] (change is +0.1 * dVbias)
Trap parameter analysis suggests voltage-vector that doesn't change field at ion:
dVbias = [1, 0, 1.31, -0.03] (V34diff change is small - ignore?)
Repeat secular measurement:
953.2 / 997.9 / 1982.1 kHz @ Vbias = [-6 0.2451 26.4101 50.0363], uMotion
(these are +315 PPM / +301 PPM / +339 PPM compared to values measured before lunch )
Ion went dark during axial scan!? (too much tickler with 20+10 dB setting!) Fluorescence recovered with detuning-scan
RID14835 C-beam, axial secular mode with C-beam, 20+20 dB
RID14836 C-beam, rhi 20+10 dB scan 995-1000 kHz (peak height 15%, could use less attenuation?)
RID14838 C-beam rlo 20+10 dB scan 950-955 kHz, 50 points (side-to-side blur at resonance in camera image, with good imagination..)
952.9 / 997.6 / 1981.4 kHz
PMT counts with 1000s gate, time-series ca 60s
feels like there is quite a lot of variation in P422
P1092 8.90 mW
422 beam power (signal-background): A 0.55-0.08 uW, B 0.90-0.15 uW, C 0.79-0.07 uW
RID14821 C-beam scan, max 21.7 kcounts, C fluorescence 8859 (1384) / 167 (16)
RID14818 B-beam detuning scan. max 12.7 kcounts, B fluorescence 5531 (228) / 64 (8) bright/dark
RID14815 A-beam detuning scan. max counts ca 21k/1000ms. A fluorescence 9342 (195) / 65 (9) bright/dark.
ID14808 detuning-scan, A-beam, 1000ms gate, -23...+10 MHz from 208 MHz set-point in 60 steps
A-fluorescence in 1000ms is 6854 (240) / 57.3 (8), repeat 5938 (281) / 67 (6)
uMotion A 7.9% in 15.9s, B 2.1% in 17.5s, C 3.5% in 14.5s
This ion loaded Monday 2021-05-17, and spent several nights + the weekend un-cooled.
07:57 ion appeared! after re-locking to Rb-line!? (ionization lasers were on also)
no ion in the trap? (tried 405nm and 461nm lasers also) tried 422 detuning-scan.
07:41Z turn on lasers
Notes on geometry and voltages
Current voltages are from uMotion optimization run 2021-05-18 ID14607 NPL search, [ 0.24512619 26.41013719 50.03631515 ], V12cm = -6 V
13:38Z: Switch off lasers for the weekend. Leave ion in the trap.
uMotions: A: 7%, B: 3%, C: 4%
12:13Z: Switch lasers on. Ion still in the trap!
15:42Z ion is still stored and cooled. Turn off lasers, leave RF on.
P1092=11mW assumed. Note new C-beam focus seems OK, almost as good as A. Matlab-code fix for C-beam (IR window transmission)
422-beam power before chamber: A 0.65-0.08 = 0.57uW, B 1.15-0.18 uW = 0.97 uW, C 0.9-0.15 = 0.75 uW
RID14790 C-beam detuning scan
RID14787 C-beam fluorescence 10743 / 220 bright/dark (note >2-fold more dark-counts! 422-scatters into PMT!?)
RID14787 B-beam detuning scan, 1000ms gate
RID14785 B-beam 1000ms fluorescence 7785 / 67 bright/dark
RID14783 detuning-scan with A-beam, 1000ms gate
RID14784 A-beam 1000ms fluorescence @ 208 MHz is 9742 / 71 bright/dark (compare to ca 90 counts for the most blue-detuned points in the scan
axial around 1.982 MHz (same as before)
uMotion A 7.5% in 13.8s, B 1.7% in 17.7s, C 4.5% in 13.5 s
last experiments ca 17 local on Wednesday, so ion stored ca 23 hours without cooling
ion appears on camera ca 6-7 seconds after opening the 422-shutter. Detuning 208 MHz as usual
12:55Z turn on lasers
Mid-shield was removed y-day, inner shield is installed
Set RF back to 10 Vpp and switch off lasers
RF 4 Vpp, Monitors: CH3: 0.720000 V, CH4 1.400000 V :
Photon correlation tickler:
Lower radial 20+12 dB:
Upper radial 20+14 dB:
Axial 20+29 dB:
Axial 0.7637 MHz
Radials 0.34 MHz and ~0.448 MHz (??)
RF 7 Vpp, Monitors: CH3: 1.200000 V, CH4 2.419999 V :
uMotions: A: 10%, B: 2%, C: 5%
Photon correlation tickler:
Lower radial, 20+10 dB:
Upper radial, 20+12 dB:
Axial, 20+25 dB:
Coarse tickler, 0+11 dB:
Radials, 0.6517 MHz, 0.7146 MHz:
Axial: 1.363 MHz
RF 10Vpp, Monitors: CH3: 1.719999 V, CH4 3.479998 V :
Photon correlation ticker:
Lower radial, 20+8 dB:
Upper radial, 20+10 dB:
Axial, 20+23 dB:
Coarse tickler, 0+8 dB:
ID14673 Radials, 0.9529 MHz, 0.99753 MHz:
ID14674 Axial 1.982 MHz
uMotions: A: 4%, B: 4%, C: 3%
Remove mid-shield and install 2nd RF-monitor probe
10:18Z Switch lasers on. Ion still in the trap!
14:36Z turn off lasers. leave ion trapped.
Install fixed 20dB attenuator. Axial with 20+23 dB
Try axial mode without fixed attenuator, 0+30 dB dds attenuation.
Too much tickler amplitude.
15:53+03 uMotion 100kphot: A 3.6% in 13.2s, B 2.7% in 20.9s, C 3.9% in 22.2s
14640, 14641, 14642 improve program so beam-letter is included in figure? (include also photons/point?)
Lower radial: (easier to excite, so peak 2-fold higher with same tickler-attenuation)
height also inversely proportional to FWHM (cooling rate) ?
Upper radial just below 998 kHz (harder to exite wrt. lower radial)
A, 0+23 dB. FWHM is large, so mode aligned along beam??
Lower radial around 952.8 kHz
Correlation with 0+23 dB attenuation
C, 0+23 dB. Peak height 0.6, too high?
B, 0+23 dB.
A, 0+23 dB.
RID14625 photon-correlation tickler, 20+20 dB, A-beam. 20kphotons/pt. inner+mid shield installed. ASI camera
A, 20+20 dB
A, 20+23 dB
B, 20+23 dB, FWHM is almost 2-fold larger than A
C, 20+23 dB,
Switch to ZWO ASI camera
uMotions at new optimum: A: 6%, B: 1%, C: 2%
ID14607: NPL search, [ 0.24512619 26.41013719 50.03631515]
Intensifier powered from Siglent lab-supply; axial:
Ion was lost?
ID14591: NPL search for uMotion minimum. 422 lost lock, fail.
uMotions: A: 8%, B: 20%, C: 22% at [-6, 0.239, 25.919, 51]
06:00Z Ion still in the trap!
Tried with another +12V source. Similar result. Investigate intensifier power box?
After removing intensifier power supply:
ID14563: Switch intensifier off:
ID14562: After installing mid-shield, now 0+28 dB:
ID14555: Intensifier on
ID14552: After installing shield, intensifier still off.
Install second half of inner shield.
ID14551: Intensifier off, second peak diminishes slowly?
Switching off intensifier, still two peaks visible? Relaxation time?
ID14543: Removed foil, now two peaks visible for C beam axial:
ID14510-13: Intensifier switched off, lower radial, photon timestamp correlation, 20+11 dB
ID14508: Intensifier: lower radial, photon timestamp correlation, 20+11 dB
ID14507: Intensifier: lower radial, 0+8 dB
Install intensifier and set to max gain.
ID14494: ZWO ASI: lower radial, 0+12 dB
Results below were obtained with ZWO ASI camera
ID14490: Lower radial, C beam, photon correlation, 20+11 dB
ID14489: Upper radial, C beam, photon correlation, 20+11 dB
ID14488: Axial, C beam, photon correlation, 20+25 dB:
ID14487: Axial, C beam, attenuation 0+25 dB. 1.9815 MHz
ID14485: Upper radial, C beam, attenuation 0+8 dB. 0.9972 MHz
ID14484: Lower radial, C beam, attenuation 0+8 dB. 0.95228 MHz
ID14482: Coarse tickler: Radials at approx. 0.95234 MHz and 0.9972 MHz
uMotions at V34diff = 51 V: A: 4%, B: 24%, C: 24%
Sweeping V34diff gives new guess for minimum for A: 51 V.
uMotions: A: 60%, B: 67%, C: 70%
11:20Z Try to load. I = 1.6 A. Ion! at 9min 30s
Check 461 dispenser. Set I from -196.83 mA -197.11 mA
10:49Z Try to load. I = 1.6 A. No ion at 10 min. Flush trap and continue. After 6 min two ions appear. Flush trap and continue. No ion for 10 mins.
Check resonator Z-matching: Minimum 1.01 at 14.4236 MHz. 1.05 at 14.424 MHz. Adjust minimum to 14.424 MHz, now 1.01.
10:29Z No ion in the trap.
14:13Z turn off lasers
uMotion A 45%, B 41%, C 46%
axial with photon-correlation, B-beam, 20+25 dB attenuation, 10 kphotons/pt.
Upper radial with correlation method. 20+11 dB attenuation, B-beam, 10kphotons/pt
coarse tickler 0+3 dB. half of axial (?) and upper radial
coarse tickler 0+14 dB, lower radial, B-beam
photon-correlation method, 20+11 dB attenuation, B-beam, 10 kphotons/pt - looks ok!?
lower radial with 0+14 dB, ca 950.7 kHz
0+14 dB artiq DDS, scan around upper radial
0+4 dB artq dds tickler shows both of these.
Upper radial scan: peak below 0.99 looks like half the axial mode, around 0.996 is the upper radial
Switch to ASI USB3 camera, to get more magnification
siglent siggen 1.8 Vpp hiZ amplitude for upper radial, manual tickler
0.996 and 0.95 MHz radial modes. Upper harder to excite.
Axial mode 0+24/26 dB attenuation
siglent siggen 280mVpp in hiZ mode - for manual tickler
coarse tickler shows resonances at 1.979 and 1.980 MHz
moving camera up/down and l/r increased PMT counts to >200/10ms (from 20/10ms)
12:36Z ion! (tried adjusting 461nm laser-current during loading)
12:14:15Z load with 1.60A
1s camera exposure
detuning to 185 MHz for loading
throw away two ions
align A-beam (not much improvement in fluorescence counts 20-40/10ms)
At 10Vpp see axial mode around 1.980 1.982 MHz
reducing trap drive to 4Vpp shows two ions
detuning to 208 MHz
11:39:15Z (ca 10mins)
11:29Z load with 1.60A (on 6.5 loading took up to 12 mins!?)
Bias voltages from previous settings -6 0.239 25.919 55 V
Detuning 185 MHz for loading
RF on, 10 Vpp drive, Rigol monitor voltage 3.46 Vpp
old camera with intensifier
11:27Z turn on lasers.
Try to record images of secular modes, to see what is causing double-peaked secular resonances?
NOTE: results below are due to filter series-resistance together with 10 MOhm input impedance of DMM!
Sanity-check of bias voltages?
V1 on bias-voltage source dispplay: -6.23901 V
V1 from bias-voltage BNC-output (no cable connected): -6.2379x V (last digit x unstable, Keysight 34461A DMM)
V1 from end of pink SMA-cable -6.2380x V (not connected to filter-board)
V1 from green screw-connector (with blue wire to trap conencted): -6.2116x V (voltage is 0.0264 V more compared to unloaded bias source? has this been measured before?)
V2 on bias-source display: -5.76101 V ( 0.5*(V2-V1)=0.239 V is the V12diff programmed - seems OK with V12cm=-6V programmed)
V2 from bias-voltage BNC-output: -5.7601x V
V2 from end of pink SMA-cable (not connected to filter-board): -5.7602x V
V2 from green screw connector -5.7356x V (0.0245 V more than from unloaded bias-source)
14:40Z Turn off lasers, leave ion trapped
back to -6V V12cm
Test with V1 and V2 bias-box outputs disconnected and V1/V2 cables terminated with 50R. Still double-peak. Now 10Vpp drive
1.783 and 1.7848 MHz
two axial modes ca 2 kHz apart seen also with siglent generator connected to piece of wire, held in front of the IR-window (IR-side inner shield removed)
Axial secular scanning with Siglent generator (no ext ref). No external attenuator. -12 dBm output (into 50 ohm). Weaker excitation ~1.559 MHz, stronger excitation ~1.5609 MHz.
RID14286 Try correaltion method with more photons 40 kphot/pt. C-beam 20+20 dB att.
8 Vpp C-beam axial, 20+9 dB att, 80 ms gate.
8 Vpp C-beam axial, 20+9 dB att, 40 ms gate. longer gate reduces false peak? measurement is long enough to show 422 power variations
8 Vpp C-beam axial, 20+9 dB att, 20 ms gate
8 Vpp C-beam axial, 20+9 dB att, 10 ms gate
ID14277 try C-beam correlation method, with a lot more attenuation 20+20 dB. 10 kphotons/pt
8 Vpp C-beam axial, 20+20 dB att
8 Vpp C-beam axial, 20+15 dB att
8 Vpp C-beam axial, 20+9 dB att
8 Vpp B-beam axial, 20+9 dB att (B should have more projection onto z?)
8 Vpp A-beam axial, 20+9 dB att
8 Vpp A-beam axial, 20+8 dB att
8 Vpp A-beam axial, 20+7 dB att
uMotion A 3.5%, B 5.7%, C 8.9%
Set RF-drive 8Vpp
9Vpp A-beam axial, 20+7 dB att. NOTE sudden shift down -2kHz(?) when working close to the trap
9Vpp C-beam axial, 20+7 dB att
9Vpp B-beam axial, 20+7 dB att
9Vpp A-beam axial, 20+7 dB att
9Vpp A-beam axial, 20+5 dB att
uMotion A 4.3%, B 4%, C 8.5%
Set RF-drive 9 Vpp
shift of about -0.5 kHz during a few minutes?
A-beam axial, 20+5 dB att
C-beam axial, 20+5 dB att
B-beam axial, 20+5 dB att
Shape of Rb-lock signal changes a lot when moving close to the laser...
Axial ca 1.9745 MHz, 20+4 dB with all beams
axial, 20+4 dB att
uMotion A 6%, B 2.4%, C 6%
Ion seems to be still trapped, fluorescence re-appears a few s after opening 422-shutter
07:23Z turn on lasers.
Turn off lasers, intensifier. Leave RF on and ion trapped
Double-peak is some nonlinear effect due to too strong tickler??
axial, 20+7 dB att
axial: lower resonance seems weaker, upper is strong with 28 dB att.
axial, 0+28 dB att
axial, 0+25 dB att
upper radial 0+8 dB att
lower radial 0+12 dB att
coarse tickler 0+8 dB shows radials ca 944 and 989 kHz. upper harder to excite.
back to V34dif=55V: get uMotion A 2.6%, B 5.9%, C 7.5%
uMotion A 68%, B 65%, C 60%
All beams illuminate ion ok
detuning to 208 MHz
13:40:30 signal - why 12 min loading-time?
13:28:30Z load with 1.60A
Detuning to 185 MHz
RF on/off to throw away the bright/dark pair
one axial mode maybe 947 kHz
sometimes shifted sideways position when scanning axial tickler
Ion jumping side-to-side seems to indicate one bright ion and one dark ion?
Axial mode ca 1.979 MHz. Coarse tickler with 0+28 dB seems too strong
uMotion A 8%, B 68%, C 44%
A-optimum at V34diff 50V
Trap voltage down to 4Vpp - no clear sign of 2 ions.
uMotion 100kphot: A 66%, B 77%, C 6% (but 11% 2nd harmonic)
A-alignment OK, B some optimization needed, C completely dark - optimization needed
set detuning 208 MHz
12:59 signal! weak cloud (not cooled?) at first - then cold and small image (later this looks like it was one dark and one bright ion)
12:53Z load with 1.60A.
405nm power ca 3.5mW
rf off/on to empty trap
12:47 no signal... check Rb-lock. check 461-dispenser 196.90 mA (close to previous setting)
12:34:30Z load with 1.60A, 1.58W initially. Detuning ca 186 MHz. Yesterday loading time was ca 4 min
Back to voltages -6.0 0.239 25.919 55 V
Install new filter-board - ion was lost during start of removal of old filter-board
Set 0 0 33.719 55 V (uMotion A 23%, B 49%, C 34%
11:03Z turn off monitor voltage logging with rigol
At 0 0.239 33.719 55 V get uMotion: A 0.6%, B 4.8%, C 5.5% - seems to confirm 1:1.3 ratio for V12cm:V34cm
Previously 1.3-fold change in V34cm gave micromotion-null. 25.919+1.3*6 = 33.719 V
Down to V12cm=0V in 0.5V steps. This gives uMotion A 70.4%, B 64%, C 67%
Voltages were -6 0.239 25.919 55 V
Try to lower abs(V12cm) before changing filter-board
Fluorescence appears again some 10s of seconds after re-locking to Rb-line.
Rb-signal changes shape a lot, and is unstable. Now quite a lot of negative DC-offset (previously positive)
10:51 cooling laser Rb-lock unlocked!?
Something in RF-drive/helres not very stable, now axial suddenly higher again, and monitor voltage also higher?
briefly seem to see 1.87 MHz or higher axial, then goes lower to below 1.86 in a few minutes!?
Axial mode with correlation method
B-beam 0+30 dB, 20 kphotons/pt
B-beam 0+30 dB, 20 kphotons/pt, wider range 1858-1863 kHz. cooling doesn't work for upper resonance!
B-beam 20+13 dB, 20 kphotons/pt, (added physical attenuator)
Check spectrum of tickler-DDS with Siglent SA. Looks OK, no visible sidebands or spurs.
With 18 dB DDS attenuation ca -8 dBm peak with spur-free SNR of ca 80 dB
correlation method for upper radial
B-beam 0+20 dB
B-beam 0+18 dB, 935-945 kHz
correlation method for lower radial. no physical attenuator. C-beam, 10kphotons/point
C-beam 20kphotons/pt, 0+16dB attenuation
A-beam 20kphotons/pt, 0+16dB attenuation
B-beam 20kphotons/pt, 0+16dB attenuation. ion not cooled at lower resonance
B-beam 20kphotons/pt, 0+20dB attenuation. ion image/cooling ok through resonance
axial secular now around 1.86 MHz (down from 1.886 MHz at end of Tuesday)
Radials ca 892 khz and 940 kHz
Upper radial is harder to excite.
C-beam 0+27dB, 10ms gate
C-beam 0+8dB, 10ms gate
C-beam 0+10dB, 10ms gate
Detuning is 208 MHz
Fluorescence counts in 10ms: A 158/4, B 111/4, C 129/6
uMotion 100kphotons: A 5% in 9.3s, B 3% in 12.3s, C 4.5% in 10.5s
07:15Z lasers on, ion seems to be still stored. camera image maybe a bit defocused?
This is maybe the 2nd (?) time ion has been stored without cooling over night?
sometime during the night, monitor-voltage dropped from 3.36Vpp to 3.2Vpp (rigol scope)
14:30Z turn off lasers. leave rf on and ion trapped
B-beam counts 66/0.22 in 10ms
B-beam power ca 0.6 uW
C-beam 0+28dB, 100ms gate
C-beam 0+30dB, 100ms gate
B-beam 0+28dB, 100ms gate
C-beam power ca 0.6 uW
C-beam ca 70/1.5 in 10ms
misalign 422 fiber-coupling (laser breadboard)
C-beam power ca 1.3 uW (too much?). Fluorescence counts in 10ms is 137/7
uMotion 100kphot: A 1.9%, B 4.6%, C 6.2%
Back to 208 MHz
0+26dB, 100ms gate
0+26dB, 100ms gate
Try detuning 185 MHz
0+26dB, 50ms gate
0+26dB, 100ms gate (note different rage)
Try changing V12cm +0.2V to -6.0, and V34cm +1.3*0.2V to 25.919V - should change axial/radial ratio?
axial 0+24 dB
axial 0+27 dB
axial 0+26 dB
axial 0+26 dB (high to low)
axial 0+26 dB (lo to high)
B-beam, sweep over both radial modes
0+8 dB now also upper radial?
Try to measure axial mode around 1.7-1.9 MHz? 0+22dB attenuation
(sweep now from high to low)
(sweep now from high to low)
(low to high)
ca 1893 and 1895 kHz.
radials were 898 and 899 kHz
A-beam, 0+10dB attenuation 0.9-1 MHz, 2000 pts, 10ms gate (down from 100ms previously). check how repeatable results are?
Zoom in on 0.88-0.92 MHz and repeat: now 0+8 dB attenuation
peaks seem to move around a lot?? changing Rf-amplitude?
further coarse-tickler scanning 0+8 dB shows peaks: ca 862 kHz, 867 kHz, and 944 kHz !?
ID13938: Maybe two peaks? Too much power?
Attempt to measure with photon correlation.
ID13933: Two-peaked lower radial now with 13 dB instead of 3 dB!
Disconnected new tickler coupling (to lower electrode). Attached old coupling capacitor to upper electrode terminal.
ID13912 photon-correlation tickler 933-935 kHz, 0+29dB att, 100pts, B-beam 10 kphot/point
ID19311: Radial (lower) sweep (coarse): 0.93236 and 0.93372 MHz
ID13903: Axial secular sweep (coarse): 1.9632 and 1.96496 MHz
ID13902: Radial (upper) secular sweep (coarse): 0.978 and 0.980 MHz
setting V34diff to 55V gives A 2%, B 5%, C 2.5%
lowering V34diff to 56V gives A 18%, B 22%, C 21%
uMotion 100kphot A 39.9%, B 42%, C 42% (1st harmonic looks ok, with only little 2nd harmonic)
set detuning to 208 MHz - image now much brighter
10:28Z load with 1.60A. 1.56W initially, ca 1.60W after 1 min, 1.607W at 2 min,
set detuning 185 MHz
no cooling during lunch -> ions seem to have disappeared?
when lowering trap-drive from 10Vpp down the glitch is between 3.6->3.5 Vpp
two ions visible when lowering trap-drive to 4 Vpp. blink-test with 405nm confirms this
uMotion A 15%, B 3%, C 3% (but 11% 2nd harmonic?)
set detuning 208 MHz
08:50 ion signal!
08:43 load again with 1.60A. Now with better 461nm current value
08:41 signal - blinking? looks like many ions, so throw away
08:27 load with 1.60 A dispenser, 461 current driver at too high set-point. Set I=-197.0mA at 10 min.
08:15Z turn on lasers
no time for trapping today, turn off lasers
no sign of ion...
08:15Z turn on lasers, check if ion is still stored?
Turn off lasers. leave RF on and dark ion trapped (until Monday?)
422 power check after detuning scans (compare to before values below): A 1.0 uW, B 1.6 uW, C 1.3 uW
Detuning-scans with improved beam alignment now looks better:
ID13862, A-beam, 1s gate. Fluorescence at 208MHz in 1s gate: 13462 / 64. scan is -23 MHz to +12 MHz from nominal detuning in 60 steps
ID13865 B-beam 1s gate. Fluorescence(208MHz, 1s): 12106 / 55
ID13868 C-beam (new!) 1s gate. Fluorescence(208MHz, 1s): 10208 / 386 (compare the dark backround count to blue-detuned values in the scan?)
uMotion now A 9%, B 3.6%, C 3.9%
aligning ASE-beam improves counts from 50/10ms up to >200counts/10ms - a 4-fold improvement.
422 beam power check: A 0.7 uW, B 1.3 uW, C 1.3 uW - similar as before.
uMotion check: A 4.9%, B 3.2%, C 3.2% - these look OK, but why are detuning-curves so bad??
Typical detuning curve:
wide scan with 0+6 dB:
With 0+6 dB attenuation also a double-peak around 933 kHz!??
Stronger tickler possibly reveals lower radial mode around 933 kHz
radial sweep, 0+17 dB attenuation. 978.3 kHz peak, 980 kHz peak (half of axial?)
tickler-spectrum with 0+28 dB attenuation:
ID13810 detuning-scan C-beam, 100ms gate. Fluorescence at 208 MHz in 100ms is 326.53/14.98 (note almost 2-fold more dark-counts with C-beam, 422-beam scatters more into camera/PMT?)
ID13807 detuning-scan B-beam, 100ms gate. Fluorescence at 208 MHz in 100ms is 285.1/6.46
ID13803 detuning-scan A-beam, 100ms gate, -23 and +12 MHz from 208 MHz. Fluorescence at 208MHz in 100ms is 355.6/7.9
Fluorescence levels (10ms) are A 35.6/0.86, B 27.8/0.72, C 35/1.24
Algorithm suggests 0.239 25.659 57.290 where we get: (100kphot) A 6.4% in 31s, B 0.6% in 36s, C 1.7% in 32s
ID13788 uMotion minimization 2x2x2 grid.
(Note NPL minimization program previously had wrong V12cm=-5V setting, now set to -6.2V as used while manually scanning)
(Note V12cm = -6.2 V is held constant)
Based on this 0.202 25.5 57.5 should be A+B optimal? Get A 11%, B 2%, C 8% ( by luck? we found also a C-optimal point!?)
V34cm 26V: A-opt (26, 57), B-opt (26, 58)
V34cm 27V: A-opt (27,56) and B-opt (27, 59)
Try same scans at V34cm=28V: B-opt (28, 60), A-opt (28, 54)
further scanning shows B-optimal point ca (V34cm, V34diff) = (29.301, 61) V . should now change something so A-optimum at (29.301, 52.5) coincides?
now A 1.7%, B 82%, C 76% at voltages 0.202 29.301 52.5
scanning V34 diff shows A-minimum at 52.5V
at this point uMotion A 48%, B 74%, C 68%
optimum found 0.202 29.301 55.057
ID13755 uMotion scan 4x4x4 grid, 50 kphot/point, estimate duration 50min (lunch)
uMotion A 8%, B 70%, C 72%
scanning V34diff shows A-min at 61V
uMotion A 64%, B 81%, C 77% (2nd harmonic content lower)
08:37:20 ion signal!
08:28 try to load with 1.60A dispenser current. Rb-lock of cooling laser seems a bit jumpy, very sensitive to air-currents above laser (shield this with alu-plate or plexi?)
trap RF OFF and the ON, to empty trap
Ions seem to be lost
08:10Z turn on lasers.
two ions were left in the trap yesterday, lasers turned off.
Blink test doesn't look great. two or more ions
Suggested optimum 0.199 23.38 65.08 - here get A 23% B 22% C 27%
ID13727 try uMotion scan 3x3x3 grid with 10kphot/point
Try detuning 208 MHz as usual?
suggested optimum 0.253 26.89 59.51. At this point A 33%, B 23%, C 21% (all with a lot of 2nd harmonic) - make sure we have only one ion!?
ID13719 try uMotion minimization with 2x2x2 grid, 50 kphot, ranges [0.2, 0.25], [26, 27], [58, 59]
Now uMotion 100kphot A 5.5%, B 36%, C 29%
Try scanning V34diff with A-beam: A-contrast minimum at ca 58.4 V
based on bias-voltage program we are now at -6.2 0.239 26.3 62.4 V
uMotion A 55% B 19% C 21% - but large 2nd-harmonic correlation, so bias voltages require adjustment
Note detuning now ca 190 MHz (because cooling didn't work previously with 208 MHz)
Install IR-side inner shield. C-beam passes through the shield hole OKish
C-beam gives ca 50 counts/10ms (maybe focus is a bit off)
Install new C-beam. Requires 0.5" extension lens-tube, so that fiber-connector doesn't interfere with Polaris M4 mounting screws
NOTE: 1.958/2 = 0.979 - so one peak in the radial spectrum might be half the axial mode?
With 0+26 dB attenuation axial mode around 1.958 MHz
Tickler with 0+13 dB attenuation shows two peaks at 0.978 and 0.979 MHz (don't know if this is the higher or lower radial mode)
uMotion A 17%, B 15%
mostly side-to-side adjustment of B-beam gives 70 counts/10ms for B also.
ca 70 counts/10ms from A-beam, very little from B-beam
detuning to 208 MHz, ionization lasers off.
CMI FLIR IR-camera monitors dispenser, and window/chamber black tape reference areas
11:00Z: Try to load, 1.7 A, Ion! after 7 min.
10:48Z: Try to load, 1.6 A. No ion after 10 min.
7:38 UTC: start working in the lab.
Check 461 dispenser: -196.95 mA, 4.462 kOhm.+
turn off lasers - not sure why loading didn't work?? :(
12:31Z no signal... dispenser off
no signal in 8-9 min, try lowering RF-drive to 4.0 Vpp (same as earlier today when loading)
12:07Z load with 1.60A dispenser (1.54W initially... rising to 1.604W)
empty trap by turning RF off, and then back on
set detuning to 185 MHz
seems ion was lost. not sure why - higher RF-voltage might give unstable trapping parameters?
ion went dark!?
Upper radial see two peaks with 0+15 dB: 1.45822 and 1.458975 MHz
Upper radial seems easier to excite?
Matlab secular predicition: 1.436, 1.469 3.06 MHz
Monitors now 5.2 and 2.16 Vpp
Set Keysight to 4.8 Vpp - 20% higher than before
Monitors 4.4 Vpp and 1.76-1.8 Vpp
lower radial 1.179495 MHz with 0+2dB
lower radial ca 1.18 MHz. Found with 0+2dB attenuation.
radial 0+10dB, 1.218889 MHz
axial again 2.490206 MHz, 20+9 dB attenuation
axial at 2.4894 MHz, 0+24 dB attenuation
with 0+6dB get asymmetric peak (too much heating)
Coarse tickler 0+10dB att finds one peak at 1.2184 MHz
Counts at 208 MHz are 43.8/1.3 in 10ms
Also try this with the lights off in the prep-room: (3-4/10ms lower background in 10ms, so 30-40 lower in 100ms?)
Repeated detuning scan with A-beam
optimizing PMT/pinhole-position gives slightly better counts 50/10ms
at -6.2 0.239 26.3 62.4 detuning-scan with A-beam shows a better slope over the detuning-range
Counts still quite low 40/5 in 10ms
(detuning scan with 100ms gate)
V34d 62.4V slightly better giving A 1.7%
at -6.2 0.239 26.3 63V get uMotion A 11% and B 31%
Further scanning V34diff shows A-minimum around V43dif=63V
NOTE: IR-side inner shield not present. Imaging this side with the FLIR camera
A-beam PMT counts 42/6 in 10ms (lights on in the prep-room give higher dark-counts)
B-beam detuning scan.
A-beam detuning scan. For secular correlation we want a large slope at 208 MHz detuning - not so great here..
Scan range (from 208MHz) is -23 MHz to +12 MHz
leave at V34diff=45V. uMotion A 50%, B 49%
Try V34diff 44..48V - no clear minimum.
Try V34diff 48..52V - optimum might be at a lower voltage
Try sweeping V34diff 52...56 V and search for B-minimum? no clear minimum
uMotion 100kphot: A 83% in 28s, B 82% in 36s
PMT counts B-beam 34.5/1.5 in 10ms (similar to A, so maybe this is due to micromotion)
PMT counts with A-beam are 39.9/1.8 in 10ms - seems a little low (micromotion, or alignment?)
Set detuning to 208 MHz - giving much brighter image
Both A and B beams give fluorescence - so their alignment is ok
dispenser off, photoionization off.
07:45 try to load with 1.60A (1.54W initially)
intensifier + PCO camera (200 ms exposure)in use. Objective attached and camera focus to "7" on the micrometer-translator. Field of view should be large, almost see top/bottom inner electrodes in image
Latest bias voltages in ARTIQ are -6.2, 0.239, 26.3, 54 V (these probably in use now). Actual voltages on device screen -6.439 -5.961 -27.7 +80.3 V
RF on at 4.0 Vpp, giving monitors 4.4 Vpp and 1.8 Vpp with Rigol scope
Cooling laser on. Rb-signal seems to wander a lot? Optimize AOM-angle for 185 MHz detuning
Keysight siggen glitches: 4.0->4.1 Vpp when moving up, 3.6-3.5 Vpp when moving down
Setting RF to max (and testing) at 11:03 UTC
Setting RF drive to nominal 2.9 Vpp at 10:36 UTC with amplifier
Setting RF drive to nominal 10 Vpp at 10:30 UTC without amplifier
Adjusted impedance matching of resonator. Now optimal SWR = 1.01 at 14.424 MHz
Setting RF drive to nominal 10 Vpp at 10:14 UTC without amplifier
Setting RF drive to nominal 2.9 Vpp at 09:26 UTC with amplifier
Using trap drive of 1.5 Vpp:
ID13539: axial: B-beam: 28.5 dB, peaks at 0.8874 and 0.89087
ID13553: radial: B-beam: 0+2.5 dB, peaks at 0.39152 and 0.388136
ID13522: radial: B-beam: 0+1 dB, peaks at 0.4431156 and 0.445226
ID13516: radial: B-beam: 0+15 dB, peak at 0.48653
Using trap drive of 2.5 Vpp:
ID13506: axial: B-beam: 0+28.5 dB, peaks at 1.4898 and 1.4922
ID13494: radial: B-beam: 0+13 dB, peaks at 0.764045 and 0.766067
ID13490: radial: B-beam, 0+2.5 dB, peaks at 0.744638 and 0.745797
ID13479: radial: B-beam, 0+3 dB, peaks at: 0.7044925 and 0.70652.
Three peaks ??? :
Leave cooling laser and ASEs on for the night. Switch off intensifier and PMT.
Switched back to 208 MHz detuning
Bias voltages: [-6.2, 0.239, 26.3, 54]
ID13382: B-beam detuning scan
Secular: correlation method with 20 dB attenuator:
ID13446: Axial 20+17 dB attenuation: split into 2 peaks approx. 2 kHz apart!
Seculars: old method: no additional attenuation:
ID13454: axial: B-beam, 0+27 dB, with 185 MHz detuning.
ID13445: axial: B-beam, 0+28 dB, peak at 1.737692
ID13423: lower radial, B-beam 0+3 dB att. peaks at 0.826577 and 0.8282684
ID13360: upper radial, B-beam, 0+13dB att. 0.8785 MHz
ID13380: Radial scan, peaks at 0.877826 and 0.880029
V34diff: 54 V, V34common: 26.3: A: 2%, B: 2%
55.6 V V34diff: A: 70%, B: 1%
ID13332: Trying lower radial with B :
Set voltages to: -6.2, 0.239, 28.0873, 52
49 V V34diff: A: 54%, B: 81%
Search for rough umotion minimum: 52V V34diff: A: 8%, B: 67%
Install inner shield ASE side (both parts of inner B shield now installed).
Ion from Monday still in the trap!
RF drive is now 2.9 Vpp, with RF amp and 35 dB input attenuation.
Switch to Rigol scope for RF monitoring.
ID13299: Trying lower radial with B :
ID13298: Trying axial with B, two peaks? :
A 63%, B 3% at V34diff = 69 V
A 4%, B 62% at V34diff = 65 V
A 32%, B 42 % (no C-beam installed)
maybe we have too much micromotion?
axial secular seems to drift higher as measurement proceeds?
12:58Z ID13266 correlation-measurement of axial, 1.724 - 1.73 MHz, 20 + 17 dB attenuation
maybe around 1.727 MHz - not so great shaped resonance..
coarse tickler 0+20 dB att axial 1.8-2.0 MHz -> somewhere in 1.72-1.74 MHz range
upper radial ca 885.4 kHz, 0+10 dB tickler att.
coarse tickler shows lower secular 833.4 kHz.
A-beam gives ca 100counts/10ms
blink-test with 405nm (low power) seems to show only one ion.
disconnect 422nm fiber to use it for aligning the PMT-splitter. Fiber-end at PMT-position, watch for centered 422-spot with the IR-side camera
Currently no PMT-splitter installed...
coarse tickler-sweep 800 kHz - 1 MHz seems to show two resonances - OK
found A-beam alignment also (at first only B-beam gave fluorescence)
12:03 signal! from B-beam? dispenser off
11:58:30 load with Dispenser 1.7A
RF signal-gen 2.9Vpp, monitors 3.12 Vpp and 1.33 Vpp
422nm A 0.7 uW, B 1.0 uW
405nm 3.5 mW
repumper 11.4 mW
clearout 62 uW
Check 461 dispenser: -197.13 mA, R 4.462
align intensifier + pco camera to inner electrodes
connect 2nd monitor to scope. monitors 4.11 and 1.68 Vpp
remove IR-side inner shield
remove outer shield, remove mid-shield
08:13Z lights on in the lab, remove finnfoam-boards
(note summer time now, UTC+3)
13:36Z dispenser off - could not get any cloud or signal visible??
12:59Z dispenser 1.66A
lab dark, intensifier to 5V, ca 400-800 ms exposure on PCO camera
422nm detuning 185 MHz
RF generator 2.8 Vpp (+attenuation + RF PA), monitor 3.1Vpp and 1.25 Vpp
re-align camera+intensifier to electrodes
Try to trap!?
17:04Z: Install all shields, and leave RF on (will switch off after midnight). RF drive voltage: 4.0 Vpp.
14:16Z Try to load, 1.65 A
13:41Z Adjust ASE,try to load, 1.65 A (1.66W).
13:14Z Adjust A-beam, try to load, 1.65 A (1.66 W). No ion.
12:49Z Adjust A-beam, try to load, 1.65 A (1.66 W). No ion.
12:10Z Adjust A-beam, try to load, 1.65 A (1.66 W). No ion.
12:01Z: Try to load, 1.65 A (1.66 W). No ion.
11:48Z: Try to load, 1.65 A (1.66 W). No ion after 10 min.
Install intensifier and ethernet camera.
10:41:30Z: Try to load, 1.65 A (1.66 W). No ion after 10 min.
10:20Z: Try to load, 1.6 A (1.56 W), RF drive 3.9 Vpp, CH4 monitor 3.02 Vpp. No ion after 10 min.
Check power: 422 A: 1.1 uW B: 1.5 uW , 461: 144 uW , 1033: 55 uW, 1092: 10 mW
Check 461 nm dispenser: T = 4.642 kOhm, I = -197.27 mA
Added 3 dB attenuation. Now 'normal' drive voltage is 3.9 Vpp (CH4 monitor 3.02 Vpp), and high is 8.9 Vpp (CH4 monitor 6.77 Vpp). Voltage can be adjusted now between normal and high without glitching.
RF generator glitches when moving from high voltage (6.4 Vpp) to 'normal' voltage (3.2 Vpp)
Logging monitor-voltages from scope failed during the night
Resonator connection, filter board and Cu tube shield had to be removed to put thermal paste
between alumina insulator and shapal heat sink.
Significant drop in monitor voltage after re-assembly was due to resonator helix being
off center, towards the trap. After centering (tuner end opened), resonance frequency
was <14.414 MHz.
After tuning, min SWR 1.01 @ 14.424 MHz, R 50.6 Ohm, X -0.24 Ohm. Q visually as before.
Monitor voltages even higher than before. Note: old monitor very sensitive to helix position,
new monitor reflects real trap voltage better?
12:42Z set to 6.4 Vpp, which gives roughly doubled monitor voltages compared to previous night
12:37Z With 6Vpp drive get monitors of 5.71 Vpp and 2.6 Vpp
12:33Z RF PA on and connected to helres with 3Vpp drive from siggen CH1
Test the RF PA. Attenuation from siggen to PA-input: 35 dB
Previously 70 mVpp (-19 dBm) from siggen gave ca 1 and 2 MHz seculars.
With 10Vpp (+24dBm) an attenuation of -35 dB gives -11 dBm (ca 178 mVpp) - OK max voltage at PA input?
siggen 3.1Vpp, 35 dB attenuation, and RF PA seems to give similar monitor-voltages as before 2.93 Vpp and 1.33 Vpp
Temperature rise with shapal heatsink and new Cu-tube.
RF 10Vpp from signal-generator, giving ca 3 Vpp on helres monitor. Seculars not measured since last helres/cu-tube changes, probably ca 0.9/1.8 MHz as usual
Trap efficiency was now estimated from a 3D FEM simulation (KH 2021-02/03), giving:
eta_in,z = 0.7264
eta_in_r = 0.7263
eta_out,z = 0.6978
eta_out_r = 0.6976
This can be compared to the old 2D cylindrically symmetric FEM result (AW 23.6.2019 and 9.11.2019, TLi notes 13.11.2019):
eta_in = 0.75
eta_out = 0.67
Installed shapal-rod heatsink, new D42mm Cu-tube, new U-shaped filter-board (with MMCX-connector for tickler)
Black tape on RF-parts for IR imaging
measured with DMM:
V1 = bottom outer electrode = -5.215 V
V2 = top outer electrode = -4.739 V
ARTIQ settings are V12cm = -5V, V12diff = 0.239 V (?check if these are the ones last used?).
Restarting clock laser to try new comb rep-rate piezo.
PDH settings were lost. These seem to work: Freq 25 MHz, amplitude 1.8 dBm, phase 51.4deg, lock level 0.0. (ARC gain notes 2020-11-21)
Composite-VGA converter for cavity camera is fried. Camera works ok with portable mini-screen.
New 1-channel Thorlabs piezo drive for Menlo comb rep-rate lock. Seems to work (check beat-note noise and compare to old data?)
buy more tape for label-maker: Dymo D1 (12mm, 0.5")
14:45Z Open cavity doors
Arrange cavity-rack in preparation for moving clock-laser seed there
shut down lasers
ion seems lost, storage time ca 11 days
stop 405nm after 10 min - still no ion
Re-lock to Rb-line, seems ok
Try all beams on and 405 nm on, repumper + clearout on
07:58Z stop B-count program.
ion went dark at some point, 04:36 local?
17:07 start B-count logging (with B-beam)
Abort A-count logging at 17:03 local.
Results from A beam fluorescence count monitoring:
Counts and ambient temperature (110 PT100):
Correlation (XY-plot) of counts and temperature:
Leave A-beam fluorescence monitor over night. start ca 15:47Z
gate 1000 ms. Should run for 24 hours.
Datafile: 2021-03-03-counts2. Note 1000ms gate-time is accurate, but there is dead-time between each data point.
09:30Z people in the lab again, may cause temperature-oscillation?
Could be related to 422nm polarization issues also?
C-beam counts, hands-off before t=300
B-beam counts when heating the fiber. Hands-off a bit before t=200. Towards end camera-image is quite weak also
A-beam counts when slightly heating the 422laser -> ion-breadboard fiber. A-beam has polarizer, which converts polarization-rotation to power fluctuations(?)
Seems low, did voltage-changes move ion out of beam-center?
Fluorescence in 10ms: A 53.76/1.82, B 22.64/1.33, C 61.05/1.95
Try again: A 12%, B 2.9%, C 2.9%
At this point uMotion: A 42%, B 49%, C 48% - user ERROR, wrong voltages applied
Optimal voltages (Common mode, diff): [ 0.23901015 28.08731594 48.19857708], V12cm = -5 V
ID13189 uMotion scan 2x2x2
uMotion A 23%, B 29%, C 32%
Voltages now at -5 0.2347 28 50.051
ID13185 z with A-beam
ID13184 z with C-beam
ID13183 rhi with A-beam - broad resonance
ID13182 rhi with C-beam
ID13181 rlo with A-beam
ID13180 rlo with C-beam
z lorentzian fit may not be very good?
ID13179 rlo scan 935-939 kHz
ID13178 rhi scan 980-984 kHz
ID13177 B-beam z-scan with 20dB, fit finally works. peak height ca 40%
B-beam tickler z-secular with 17 dB gives 60% high peak - and fit fails - maybe more attenuation needed
lorentzian fit to z-secular with A-beam seems difficult..
ID13172 try z-secular with A beam again, 27 dB attenuation - but fit fails again.
ion still stored
No experiments during the night
Leave B-beam on.
Summary: Seculars with -5 0.2347 28 50.051. A-beam
axial/radial ratios ??
z-scans where lorentzian fit failed:
Note these are also asymmetric/hysteretic. we sweep the tickler from low to high frequencies
ID13170 try again with 23 dB DDS attenuation (up from 17 dB) - fit fails for the 3rd time
ID13169 narrower range 1843-1844.5 kHz - too strong tickler gives blurry image? may not give lorentzian resonance? - fit fails again!??
ID13168 fit fails :(
ID13168 z scan 1842-1846 kHz - peak up to 50% with blurry camera image. As predicted A cools z-secular badly, so resonance is narrow
z search 1840-1860 kHz - found at 1844!
old z(-6.1)=1876 kHz and z(-6.2)=1879 kHz, so expect z(-5) at -33kHz around 1843?
ID13166 rhi scan 980-984 kHz - as before, rhi resonance is broad with A-beam
rhi search 970-990 kHz - found around 982 kHz
previous rhi was 954 kHz, so expect it around 985 kHz maybe?
ID13164 rlo scan 935-939 kHz
930-940 kHz - peak at ca 936.5 kHz - ca +31.5 kHz from last value with V12cm=-6.1V
search 920-930 kHz - no peak
search 910-920 kHz - no peak
tickler search 900-910 kHz (previous rlo was 905 kHz) - no peak found. 0.1V change in V12cm moved r-secular 3 kHz yesterday, so expect 30-33 kHz now?
Using A-beam for these tickler measurements
Go back to -5 0.2347 28 50.051 - uMotions A 2%, B 9.9%, C 13%
At this point: A 46% !!, B 2.3%, C 16% - repeat A 46%
Optimal voltages (Common mode, diff): [ 0.19201393 27.06730014 49.21492668]
ID13146 uMotion scan 2x2x2 grid
at -5 0.2347 28 50.051 get uMotion A 2.8%, B 11.5%, C 12%
Try scanning V34cm, A-minimum at 28 V
Now uMotion A 38%, B 27%, C 31%
Try reducing V12cm to -5 V. Other voltages as before 0.2347 26.7769 50.051
ID13112 uMotion scan with 5x5x5 grid
Optimal voltages (Common mode, diff): [ 0.23465246 26.7769039 50.05097994], V12cm=-6.1 V
At this point A 2.9% in 16.3s, B 2.2% in 13.4s, C 2.6% in 21.9s
ID13106 uMotion scan 2x2x2
scan gives Optimal voltages (Common mode, diff): [ 0.18054628 26.89479311 50.30482989]
At this point get A 3.9% in 20.5s, B 12% in 16s, C 4.4% in 19.8s
at -6.1 0.2277 26.3891 51.2 get uMotion: A 6.7%, B 22%, C 25%
Sweep V34 diff: A-min at 51.2 V
uMotion (100kphot): A 70%, B 71%, C 72%
Fluorescence (10ms): A 74.27/1.48, B 114.38/1.34, C 66.76/1.98 (lab lights are off)
after ca. 1 min of 405nm irradiation - ion re-appears!?
re-lock to Rb-line
08:54Z ion seems dark
After a stable period, lab temperature oscillates again?? why?
16:52 leave lab.
Leave A beam on. No experiments during the night
Maybe Rb-lock was OK?
Now A 97.6/2.13, B 38.85/1.62, C 74.11/1.93
Try re-locking to Rb-line
repeat A 93/1.9, B 98/1.47, C 72/1.66
Fluorescence (10ms): A 86/1.6, B 90.67/1.43, C 64.57/1.61
What if we try to minimize micromotion at V12cm = -6.1 V? Previosly V34cm change was -1.3 V34cm/V12cm
ID13058 uMotion scan 2x2x2 grid
B gives really low fluorescence suddenly? 50 seconds to measure 50 kphotons
Optimal voltages (Common mode, diff): [ 0.22771198 26.38907221 56.11298177] (note previous V34cm was 26.18V so this is now higher?)
At this point get 100kphot uMotion A 7%, B 2.1%, C 1% (ca 21-22s measurement time with A and C, but with B 102s)
Tickler measurements now with A-beam
ID13064 z-scan, with -6.2V was at 1876.4 kHz (B-beam in use, tickler program sets beam!?)
A-beam fluorescence also quite weak, laser Rb-lock possibly jumped? (to next Rb-line +60 MHz more detuned?)
Previous peak-height was just over 30%, now get 60% because of less efficient cooling/damping?
ID13065 rhi scan 952-956 kHz - previously at 953.9 kHz. Now with A-beam, giving very broad resonance (A cools rhi well?)
ID13066 rlo scan 903-907 kHz - previously at 905.1 kHz. Note FWHM is almost 3-fold narrower
ID13053 better z-scan
z scan 1870-1880 kHz - found just above 1876 kHz
rhi scan 951-961 kHz - found at 954 kHz
rlo shifted up by +3 kHz, around 905 kHz
ID13047 900-904 kHz rlo scan
Try V12cm = -6.1 V (no change in other voltages)
uMotion A 8.6%, B 19%, C 21%
Tickler measurements with B-beam
axial/radial ratios 1.967 and 2.073
axial/radial ratios 1.976 abd 2.083
with V12cm = -6.2 V , seculars today are:
ID13045 rlo scan
ID13044 search for rlo 897-907 kHz - 1% higher than Friday would be 902.8 kHz - found at just over 902 kHz
ID13043 scan 949-953 kHz
ID13041 rhi search 940-950 kHz. same scaling would give 946.7 kHz - found peak at 951 kHz
ID13040 1876-1882 scan.
ca 0.55% higher than on Friday
ID13039 search 1870-1880 kHz. 10 kHz/30 pts = 333 Hz step - peak around 1879
Search for z-secular 1860-1870 kHz
at this point A 4.0%, B 2.2%, C 1.2%
Optimal voltages (Common mode, diff): [ 0.23807795 26.17776091 57.07942005], V12cm = -6.2
ID13032 uMotion search 2x2x2 grid
ca 57V seems better, uMotion A 13%, B 40%, C 43%
previous V34diff was 49.8V
uMotion A 75%, B 74%, C 72%
Fluorescence A 122.37/1.85, B 119.98/1.83, C 82.64/1.95
install inner shield camera side, and mid shield
With old objective, when focused to Z=7mm, gap to vacuum window is ca 5mm
However image with new objective not so great :( so go back to old objective
Try new objective: focus is closer to Z=6mm, and new image ca half screen to the right of old objective (as viewed in ASI camera software)
For old imaging objective XYZ Z=7mm translator X=55, Y= 36<->0
got C-beam aligned, via electrode diffraction pattern (only inner shield installed)
aligning C-beam with mid-shield installed seems difficult
ca 12-12:30Z (14 local) work in the lab (check how temperature responds?)
Ion stored for ca 1 week now
07:13:00Z Stop collision monitor.
16:03Z start collision monitor. B-beam, detuning 208 MHz, fast 3 ms gate. Threshold set as 40 bright 1 dark (artiq sets geometric mean of these?)
clearout is on
NOTE: scripts assume 10ms gate time, use last column (machine unit) for analysis
B fluorescence in 10ms: 157/1.14, in 5 ms: 71.97/0.44, in 3 ms 44.27/0.42 - lab lights are off
Set RF drive to 10 Vpp
uMotion A 2.8%, B 2.6%
Summary of secular results (Compare to 2020-12-09)
Z-frequency 94.95% of Dec value, with voltage-slope 93.09% of Dec value
rhi 95.55% of Dec value, with voltage-slope 93.37% of Dec value
rlo 95.05% of Dec value, with voltage-slope 93.90% of Dec value
Set RF drive to 9.0 VPP.
z maybe 1681 kHz? found at 1675 kHz
rhi maybe 836 kHz? found at 852 kHz
rlo maybe 800 kHz?
Set RF drive to 9.5 VPP. Expect 95% of 10Vpp seculars?
z ca 1775 kHz? actual resonance ca 1771 (94.8%)
rhi maybe 888 kHz? found at 897 kHz
rlo maybe 843 kHz? found at 847 kHz
lower radial slightly lower than expected, below 894 kHz
Try to find r_hi 934-940 kHz
Behold, artiq autogenerated figure output from the correlation tickler secular sweep program
(these measured with the usual 10Vpp RF drive, B-beam, fixed 20 dB physical atteunator on dds-output, software attenuation adds to this)
ID12911 same scan, modify lorentzian fit to match matlab 'lorentzfit' functional form. resonance at 1868.59
try 1866-1870 kHz - 22% peak at 1868.6 kHz
ID12909 secular z-sweep, B-beam, 1862-1866 kHz
RF monitor 3.06 Vpp
uMotion A 1.8%, B 3.4% (C not aligned to ion...)
Set -6.2 0.2445 26.9255 49.8
scan V34diff, A-optimum at 49.8V
uMotion: A 37%, B 28%
C-beam alginment seems lost...
Fluorescence countsin 10ms are: A 97.8/1, B 106.4/1, C 42.2/1.5 (lab lights are off)
Detuning back to 208 MHz
11:59 stop collision monitor
11:58Z ion still stored. fluorescence quite weak
lights off, leave lab.
16:49Z start collision-monitor ID12879, DB 2021-02-25-run1
B beam, Counts / 10 ms: Bright: 35, dark: 3.
Detuning 190 MHz. Clearout on
Set detuning to 190 MHz, giving ca 30-40 counts in 10ms
Use B-beam (may have polarization issues? correlates with lab-temperature?)
uMotion A 4.8%, B 5%, C 2.8%
Set voltages -6.2 0.2445 26.9255 51.6
Scan V34diff, A-minimum at 51.6V
uMotion A 12%, B 11%, C 11%
Counts A 141/4, B 62/3, C 103/4
Try I1 = -8.6056, I2 = -1.0049, I3 = 7.0059, giving abs(B) =
ID12845 peak search with 300us
C1+ 18%, C1- 32%
C1 B estimate = 2.055935940628926
C1 Linecenter = 75.97028908312774
NOTE: B-beam fluorescence down to 53.57/3.17, indicating maybe Rb-unlock? (or polarization-effect giving unbalanced C+ and C- peaks?)
Try I1 = -8.6056, I2 = -3.0049, I3 = 7.0059, giving abs(B) = 2.2646, 2.2526, and uT
ID12842 peak search, 300us. Should now compute line-center and B after each pair
C1+ 24%, C1- 64% (!)
C1 Linecenter = 75.97024614563541
C1 B estimate = 2.2646399566052304 uT
C2+ 24%, C2- 14%
C2 Linecenter = 75.97025830181504
C2 B estimate = 2.2525933966917435
ID12840 peak-search with 300us, and new B-estimate 2.119 uT
C1+ now lower 29%, and C1- higher 53%
C1 Linecenter = 75.97016610304007 MHz
C1 B estimate = 2.1102318715100816 uT
C2+ 45%, C2- 19%
re-initialize search with C1 line-center and B-estimate
ID12838 peak search, 300us probe, with B=2uT estimate
C1 Linecenter = 75.97022862199493 MHz
C1 B estimate = 2.119082202980859 uT
Set coil currents I1 = -8.6056, I2 = -2.0049, I3 = 7.0059
TLi notes on Magnetic Field (2021-02-15)
For B-beam, using A-matrix and B0 residual field from 2021-01-21.
Should give equal C1/C2/C4
abs(B) I1 I2 I3
2 -8.6056 -2.0049 7.0059
3 -10.672 -2.5016 9.9934
4 -12.739 -2.9984 12.981
ID12835: Peak search without OD filters, B beam. clock_probe = 300 us
C1 Linecenter = 75.97019812711028
C1 B estimate = 1.046407999323715
ID12831: Rabi flopping on B beam, no OD filters. tau_pi ~ 300 us.
Problem with comb rep-rate lock
The closed-loop rep-rate error signal started to show glitches, with about 400-500ms period
This caused all SDR counter-data to be flagged invalid
A Thorlabs MDT693 Piezo-driver was tested - and showed no glitches
Also the cable from the rep-rate lock-box to the piezo driver was replaced!? (suspect looking ends??)
With the new cable, also the old Piezo driver seems to work? (since about 15:25 local, at least for about 10 minutes)
Leave it running, to see if problem re-appears
however the problem re-appears after a 10min warm-up period!!??
14:08Z Go back to the Thorlabs driver. This gives glitch-free lock and valid SDR-counter data
after lunch fluorescence seems weak. Re-locking to Rb-lines improves counts 3-fold
At this point get: A 1.3% in 11s, B 0.9% in 15s, C 0.8% in 15s
Optimal voltages (Common mode, diff): [ 0.24445048 26.92545019 51.96431002]
ID12794 uMotion search 4x4x4 grid
ID12793 repeat - [2.90072747e-02 2.89735223e-04 1.86382763e+00 2.69222756e-04], Lorentzian FWHM = 2 g = 538.4 Hz
ID12792 scan 1862-1866 - 30% just below 1864 kHz - Lorentzian fit: [2.33235839e-02 3.39371929e-04 1.86379851e+00 3.83917947e-04] (constant, amplitude, f_center, gamma)
ID12781 search for z-resonance at higher frequencies 1856-1866 kHz
ID12790 tickler-correlation, z - no resonance
These can be cropped to show only the ion by:
convert 2021-02-25_A_15s.jpg -crop 150x150+1050+120 A4.jpg
Ion images with different beam combinations:
15s stack of 1s exposures. Old imaging objective, ASI camera, high-gain, no binning (1936x1096 pixels). Pixel size is 2.9 um x 2.9 um. Estimated magnification is 30x
Fluorescence levels (10ms): A 132.1/3.8, B 127.6/4.2, C 75.8/4.0
Multiple beams: AB 117.7/4.2, BC 154.4/4.3, AC 143.0/4.6, ABC 181.85/4.6
uMotion A 2%, B 0.9%, C 6.1%
Set -6.2 0.23 26.8378 52.4
sweeping V34diff shows A-minimum around 52.5V, finer resolution sweep gives 52.4V
uMotion A 47%, B 45%, C 49%
Voltages now: -6.2 0.23 26.8378 55
Increased AC-setting at 30 Hz gives slightly higher amplitude oscillations, compared to weekend setting of 25 Hz
Weekend had less heat load in the lab
07:37 stop collision monitor
07:36Z ion still stored
ID12763: Start at 14:48:52 UTZ: Collision monitor with clearout on, with B beam. Tag: 2021-02-24-run1
Counts / 10 ms: Bright: 121, dark: 3.
usual detuning for operation, 208 MHz (check?)
AC setting now increased to 30 Hz
Sweeping V34_diff gives new 'optimum':
uMotion A 4.1%, B 1.2%, C 6.1% at [-6.2, 0.23, 26.8378, 55] (down 1.6V from morning value of 56.6V)
uMotion A 30% in 12s, B 30%, C 36% at [-6.2, 0.23, 26.8378, 56.6]
re-lock to Rb-line -> fluorescence restored!
14:33 ion seems dark/gone?
ID12745 test2 of secular scan Lorentzian fit: [2.00147896e-02 2.50019692e-04 1.85449329e+00 3.99132412e-04]
ID12744 test of secular scan with constant+Lorentzian: [2.17395264e-02 2.64289160e-04 1.85434871e+00 4.59689160e-04] (constant, amplitude, f_center, gamma)
Compare this to Matlab fit to same data points?
Try the third (lowest) piezo-channel of the driver. This again initially gives ok comb-lock and beat-note data - but after 1-2 minutes glitches appear again!
rebooting the rep-rate piezo driver seems to remove the glitch - however the problem appears after a few minutes again
Comb rep-reate lock shows 400ms heart-beat error, can't determine line-center from comb data....
ID12736 carrier C1 peaks with 600us probe
+C1 ? see two peaks?
Now optical carrier and side-bands
ID12739 z 1.848 - 1.856 MHz, Lorentzian fit: [3.72032165e-04 1.85437750e+00 6.67644320e-04]
ID12738 r_hi 937-943 kHz,
ID12737 r_lo 885-892 kHz,
(these over lunch). more points and 100 kphotons per point
ID12734 r_lo 885 to 891 kHz, 7 dB - 22% peak at ca 889.6 kHz - Lorentzian fit: [3.85734824e-04 8.89606990e-01 5.82098050e-04]
ID12733 r_hi 937 to 943 kHz, 7 dB - 16% peak at ca 929.1 kHz - Lorentzian fit: [2.93961269e-04 9.39172793e-01 7.09967596e-04]
ID12731 z 1849 to 1855 kHz, 17dB - 22% peak at ca 1852.1 kHz - Lorentzian fit: [3.88708773e-04 1.85215658e+00 6.40710257e-04] (curret ARTIQ fit doesn't have constant background term)
ID12730 r_lo 891 to 897 kHz - no clear peak
ID12729 secular correlation search 943 to 948 kHz, 7 dB att - no clear peak
B-beam in use, 50 kphotons/point
RF monitor ca 3.040 Vpp (slightly lower than y-day?)
Fluorescence levels (10ms): A 139.2/1.56, B 126.46/1.1, C 110.8 / 1.9
At -6.2 0.23 26.8378 56.6 get: A 1.4%, B 3.1%, C 8%
Scanning V34diff shows A-minimum at 56.6 (scanning only V34diff seems to be a quick way to find the optimum from day to day!?)
Maybe V34diff has settled to a lower value again?
uMotion 100kphot: A 74% in 9s, B 73% in 9s, 75% in 9s
Voltages -6.2 0.23 26.8378 63.3441
08:23Z ion still stored. secular sideband measurements completer over night
15:21Z leave lab
ID12705 z, search21
ID12704 r_hi, search20
ID12702 B-beam r_lo, search19
ID12701 switch to B-beam
ID12700 z, 2 kHz AOM span, search18
ID12699 r_hi, 2 kHz AOM span, search17
ID12698 r_lo sidebands, 2 kHz AOM span, search16
ID12697 z sidebands, search15
ID12696 r_hi sidebands, search14
ID12695 A-beam, r_lo sidebands, wider 1 kHz AOM span, 16 Hz AOM step, C1+ and C1-, 5 ms probe (no OD filter). DB: search13
63 points per peak
C1+ red appears far right in span?
ID12690 r_lo sidebands
uMotion A 66%, B 64%, C (very weak)
ID12676: Photon correlation secular sweep for higher radial: 20 + 7 dB att. Peak at approx. 0.9447 MHz.
ID12675: Photon correlation secular sweep for lower radial: 20 + 7 dB att. Peak at approx. 0.8942586 MHz.
ID12674: Photon correlation secular sweep for axial: 20 + 17 dB att. Peak at approx. 1.8524828 MHz.
ID12673: Secular sweep with 0dB + 22 dB: Lower radial ~ 0.89449 MHz, upper radial ~ 0.94558 MHz
ID12672: Secular sweep with 0dB + 20 dB: Axial: peak at approx. 1.8528 MHz
ID12665: Carrier search for C1, tau_pi = 600 us. 2021-02-23-search11-
ID12659: Carrier search for C1, tau_pi = 600 us. 2021-02-23-search7-
12657: C1+ red low radial?
12658: Rabi on previous. Tau_pi maybe 5000 us
ID12654: Secular search for C1, 2021-02-23-search4-
Tests with objective, umotion again high! V34diff needs 10 more Volts to get uMotion acceptable (sharp camera image)
New imaging objevtive did not show a good image... further testing required
Here uMotion A 0.3%, B 1.1%, C 2.5%
Back to -6.2 0.2358 26.8378 48.3441
ID12569 tickler 20+17 dB, 1864 - 1868 kHz, 30 points - no peak..
At these voltages get 100kphot: A 9.2% in 9s, B 3.4% in 10s, C 5% in 12s
Optimal voltages (Common mode, diff): [ 0.2358202 26.83783696 48.34408991]
Test how trap parameters change at V12cm of -6.0V (previous setting was -6.2V 0.2289 26.8187 48.4554)
ID12562 uMotion scan 4x4x4 (lunch) - USER ERROR: this scan at V12cm=-6.2V as previously....
Note matlab lorentzian fit is variant '3c' of lorentzfit:
L3C(X) = P1./((X - P2).^2 + P3) + C
FWHM is computed as:
FWHM = 2 * sqrt( P3 )
fine-resolution correlation measurement of seculars (now with B-beam)
ID12555 scan 890-893 kHz, 30 points, 20 + 7 dB attenuation - peak height up to 40% contrast
ID12556 scan 937-941 kHz, 30 points, 20 + 7 dB attenuation - peak height 14 % (upper radial is harder to excite with tickler - as before)
ID12557 scan 1.864 - 1.868 MHz, 20 + 17 dB attenuation - peak height 30%
RF monitor during these 3.045 - 3.048 Vpp
search for seculars (A beam)
tickler 0 dB + 15 dB attenuation - no clear fluorescence change. search 0.9 to 1.1 MHz
0 dB + 10 dB attenuation
0 dB + 5 dB attenuation. one mode at 939.6 kHz
0 dB + 2 dB attenuation: lower at 891.4 kHz, upper at 939 kHz
0 dB + 20 dB for axial, 1.8-2.0 scan, at 1.86644 MHz
500kphot A 1.8% in 41s, B 1.3% in 49s, C 3.7% in 61s
100kphot A 1.3% in 9s, B 0.9% in 10s, C 2.9% in 13s
found Optimal voltages (Common mode, diff): [ 0.22887765 26.81872373 48.45535893]
ID12530 2x2x2 uMotion search
Voltages at -6.2 0.2832 27 47
uMotion 100kphot: A 17.6% in 9s, B 17.3% in 10s, C 32% in 12s
Fluorescence levels (10 ms): A 160.7 / 2.14, B 133.59 / 1.94, C 98.25 / 2.04
back to 208 MHz detuning
08:31Z stop collision monitor
ID12517: Start at 15:00 UTZ: Collision monitor with clearout on, with all beams, detuning = 190 MHz. Tag: 2021-02-22-run1
Counts / 10 ms: Bright: 79, dark: 3.
reducing RF-voltage to 4.1Vpp doesn't show two ions - so this is probably a single ion
These are higher than previously during collision-monitoring/clock-runs (ca 60-70 bright counts?)
10ms fluorescence levels A 166.5/2.25, B 145.54/1.94, C 109.88/2.54
all beams ABC show fuzzy image, any single beam sharp image?
uMotion A 14% in 9s, B 9% in 11s, C 22% in 11s
14:39:30 signal (in 3 min)
bias voltages -6.2 0.2832 27 47
RF back to 10Vpp
14:36:30Z try load with 1.60A (1.54W)
changing V12cm from -6.2V to 0V in a single step threw the ions away
reduce RF to 4.0V increases ion-separation clearly on camera
14:30:05Z signal, blurry at first, then two separated ions
14:23Z try to load with 1.65A. detuning 185 MHz, 405nm was up to 7mW - reduce to 3 mW
lowering RF-voltage shows up to three ions! (saved some images)
detuning to 208 MHz
14:16Z signal! fuzzy image
back to voltages -6.2 0.2832 27 47
14:11:15Z load again, 1.7A, detuning to 185 MHz
adjusting RF-voltage down -> maybe two ions in the trap? lost both at RF-glitch
bright ion seems to jump between two positions?? (when switching beams) do we have two ions trapped?
-6.2 0.2831 27 42.4 gives A 15%, B 2.2%
-6.2 0.2832 27 Scan[41 43] B
-6.2 0.2832 27 Scan[38, 43] gives A-optimum at 42V
A 65%, B 68%, C 70%
Optimal voltages (Common mode, diff): [ 0.2778 26.13 47.58]
ID12458 2x2x2 uMotion scan
[0.25, 0.32] [26, 27.5] [46.5 48.5](too large?)
uMotion A 70% in 8s, B 64% in 11s, C 70% in 11s
Voltages -6.2 0.2832 27 47
Lowering trap RF to 5.7Vpp gives stable high fluorescence, 1200 couns / 50ms all beams
try different V34diff voltages, but no clear effect
seem to have something trapped, but fluorescence comes and goes
13:39:35 signal, but fuzzy image of ion? gone quickly?
13:35:30 try to load, 1.7A, detuning to 185 MHz
13:32:15 signal! but lost quickly?
13:26:15 load with dispenser 1.7A. test loading with 208 MHz detuning?!
back to volgaes
ion lost during uMotion search?
ID12410 seems to have finished ok?
fit fails because V34diff range was [46.5, 46.5] (no scan at all)
not so reasonable Optimal voltages (Common mode, diff): [ 1.80241039e-15 9.93688436e-17 -2.15053763e-02]
ID12410: NPL search 2x2x2.
Optimize beams and 422 waveplate.
0.2832 27 47 gives A 14%, B 9%, C 21%
0.2832 28.1299 47 gives A 28%, B 26%, C 40%
0.2832 28.1299 46 47 gives A 28%, B 26%, C 40%
ID12380 scan V34diff vs A-contrast. Minimum at ca 47V
uMotion 100kphot A 76% in 9.9s, B 70% in 16s, 71% in 15s
ASE also required re-aligning, got >2-fold more fluorescence (all beams) by aligning ASE
uMotion 100kphot: A 81% in 22s, B 76% in 27s, C 75% in 29s
B > 200 counts in 50ms, C was already quite well aligned, up to 280 / 50 ms afer adjustment
re-aligning beams is required, since V34dif changed som much? 3-fold more A-fluorescece ca 300counts in 50ms
check Rb-lock, locking to the right line gives better fluorescence
422 power only 5uW on breadboard before A-fiber (this usually 10-15 uW), adjustment of 422 breadboard fiber-coupling gives ca 9uW
lowering V34diff to 53V gives the usual diffraction-pattern image of ion
detuning to 208MHz
12:05:50 some weak signal? (ca 3 min loading time - good!?)
12:02:45 load with dispenser 1.7A
405nm adjusted to 3.7 mW
422nm 185 MHz detuning
461nm dispenser test, Ractual 4.642 kOhm, -197.32 mA, test against 5A dispenser ca 2 min to see fluorescence.
RF monitor 3.045 Vpp
Voltages to last known values: -6.2, 0.2832, 28.1299, 85.6211
camera focus back to last value
11:52Z install mid-shield, and imaging objective
08:20Z turn on stuff to prepare for trapping again
Menlo oscillator was on continuously.
A/C VFD was at 25 Hz
With most stuff turned off on Friday, see strange oscillations in lab temperature
Leave the RF siggen on/off program on
Clamp down helres trap-side
Trim 3mm off the helres-mount clamp
Before final fine-tuning, vswr with newer rigexpert analyzer:
Helical resonator min SWR was 1.12 @ 14.422, which probably explains
lower seculars (qz). HR moved a few mm to the left and towards the trap
and rotated ~0.5…1 deg CW seen from tuner end to center helix and to
align shield adapter with trap Cu pipe.
Also 0.1 mm soft Cu shield replaced by stiffer 0.2mm Cu. This increased
Vmon (helix moved closer to antenna) and required tuning and impedance
After: min SWR = 1.01 @ 14.424 MHz and Vmon = 2.995 Vpp (averaging 32).
R = 50.2 Ohm, X = 0.15 Ohm, Q ~ 800 as before.
NOTE: adjusted A/C to 25 Hz - to possibly reduce temperature swings?
detuning to 185 MHz, 461nm and 405nm lasers on - but no ion?
08:08Z Ion seems lost? Rb-lock was unlocked (large temperature-swings in lab!?), re-lock, but this doesn't restore fluorescence
NPL uMotion program had aborted, due to ARTIQ error? (because of Rb-unlock, or ion loss?)
Leave 8x8x8 uMotion scan over night
ID12326 ranges [0.1 0.4] [26 30] [80 90]
16:09Z uMotion 100kphot: A 34% in 8.7s, B 31% in 14s, C 24% in 9.7s
The required V34diff might be drifting down during the day?
TLi computed from these: qz=0.3643, a=(-0.00038, 0.0016, -0.0012)
These measured with 10Vpp drive, ca 2.70 Vpp helres monitor, and fixed -6.2 V12cm
Reults to be plotted + Lorentz-fit: axial ID12318, r-lo ID12320, r-hi ID12322
upper radial with photon correlation. B-beam
ID12321 978 to 982 kHz, 20+7 dB att, 10 kphotons
ID12322 with 50 kphotons/point
lower radial mode with photon correlation. B-beam
ID12319 923 to 927 kHz, 20+10 dB att, 10 kphotons
ID12320 20+7 dB att, 50 kphotons
fine-resolution secular scan using photon correlation. B-beam. ( 2020-12-09 results use 13 dB for radials and 21-23 dB for axial)
search areas at 925, 980, and 1892.5 kHz.
use the physical 20dB attenuator
ID12312 1.89 to 1.895 MHz in 30 steps, B-beam, 10 kphotons per point, 20+22 dB attenuation
ID12313 20+26 dB attenuation, 20 kphotons, - too much attenuation, peak height low
ID12314 20+23 dB attenuation - 0.2 peak height
ID12316 20+20 dB att, 10 nbins,
ID12317 20+17 dB att, 0.3 peak height ok? but peak looks a bit noisy?
ID12318 20+17 dB att, 50 kphotons/point (ca 6-7 s/point)
Coarse search for secular frequency.
20dB physical attenuator on tickler-DDS. 0 dB software attenuation
resonance at ca 1.892 - 1.894 MHz ca 96% of 2020-12-09 result (lower than before, 2020-12-09 result with 10Vpp drive is 1.968 MHz)
Try 6 dB sw attenuation, resonance at 1.892-1.893 MHz.
(2020-12-09 results have radial modes at 985 and 940 kHz, or 50% and 47.8% of axial)
This would predict current radial modes at 947 and 904 kHz
tickle 0.85 - 1.0 MHz, 6dB, 400 points, but no clear signal (50ms PMT gate).
Try 0dB , also try 100ms gate, remove 20dB physical attenuator and use 15 dB sw attenuation
with 10dB sw-attenuation, one mode at 925 kHz?
try 5dB attenuation, try 0 dB attenuation -> this reveals upper mode at 980 kHz!
B fluorescence 75.7 / 3.96 in 10ms (mid-shield installed, back lab lights on)
B intensity still changes with polarization! Adjust waveplate again.
uMotions: A: 37%, B: 33%, C: 31%
ID12264: Peak search, B-beam, no OD-filters. 2021-02-17-search6-.
C1 linecenter: 75 971 017.0 Hz
C1 B estimate: 1.2443346 uT
ID12258: B-beam Rabi flopping, tau_pi = 0.6 ms:
Adjusting waveplate on 422 breadboard reduces fluorescence change to negligible levels:
Heating B or C fibers by hand seems to give >50% fluorescence change
ID12245 peak search A-beam 350us, no OD filters
C1+ ca 75 974 7, height ca 40
C1- 75 967 5, height 60
Found C1+, rabiflop shows maube 350us tau_pi with A-beam?
seems Zeeman AOM diffraction-order was wrong. Switching to right one gives quantum-jumps as expected.
ID12238 spectrum-scan with 1ms probe, no OD-filter, A-beam
beat-note and excel-sheet suggest line-center around 75.971 150 MHz
Coil currents (-8, 0, 0) mA - same as previously?
A-beam fluroescence 97.4 / 2.4 bright/dark in 10ms
Try to search for the clock-transition?
At this point get: A 3.8% in 13s, B 2.9% in 10s, C 2.4% in 19s
Optimal voltages (Common mode, diff): [ 0.2832 28.1299 85.6211]
ID12223 Try 2x2x2 uMotion scan?
V0 - 0.33VA = 0.2610 27.8855 87.2692, here get A 27.5 %, B 29.8%, C 36.3% - ??
maybe -sign is right?
V0 + 0.33 VA = 0.2612 28.1501 87.5210 here get A 39%, B 29.6%, C 35.5 %
Try moving along voltage-vectors to zero uMotion?
uMotion 100kphot: A 33.8% in 15s, B 29.4% in 12s, C 36.7% in 13s
detuning constant at 208 MHz
Rb-signal has a lot of DC-offset, so this may give some extra detuning?
Re-lock to Rb-line, this gives ca 5-fold more fluorescence and brighter camera image
uMotion 100kphot A 9.7% in 91 seconds!?, B 9.0% in 95s, 11% in 85s
Fluorescence level seems low? camera image weak..
Comb f0 unlocked due to low SNR. re-locked
ID12186: 4x4x4 NPL search around previous value.
Result: [ 0.26114758 28.01782364 87.39507497]
uMotions at optimum: A: 3.6%, B: 5.5% C: 9.2%
Check that the columns of inv(Cfit) are voltage-vectors that change only one contrast!?
% Micromotion contrast model
% S = C (V - V0)
% S has [A, B, C] contrasts
% V and V0 have voltages [V12dif, V34cm, V34dif]
% V12cm is constant -6.2 V in recent experiments
-0.9303 -2.0943 -0.4214
-0.2217 0.1219 -0.1284
-0.1447 -0.1542 0.1619
inv(-1*Cfit) = % sign is arbitrary..
-0.0004 2.9735 2.3561
0.4009 -1.5572 -0.1910
0.3815 1.1746 -4.2519
Cfit * [-0.0004 0.4009 0.3815]' = [-1 0 0]'
moving along first column-vector of inv(Cfit) changes A by 100% and leaves B and C unchanged.
Cfit * [2.9735 -1.5572 1.1746]' = [0 -1 0]'
Cfit * [2.3561 -0.1910 -4.2519]' = [0 0 -1]'
Manually: 29%, 30%, 31% at [0.25, 29.4, 87]
Manually: A: 53%, B: 1%, C: 21% at [0.3306, 27, 86]
ID12094 leave uMotion scan over night
8x8x8 grid. voltage ranges [0.5, 1.5], [20, 30], [95, 105]
Result: (Common mode, diff): [ 3.99139299 12.57404019 85.31937744]
1 scanned 25.8, 98: A-optimal (A 1.9%, B 74%, C 40%)
1 25 99 seems roughly A-optimal (A 7% B 65% C 8.4%)
go back to the AC-optimal 1.0 25 100: A 9.7%, B blur 62%, C 7.1% - so AC-optimal point is roughly repeatable
but scanning V34diff or V34cm around here gives more or less the same flat A-contrast values
at 0.3 27 48 get A 21% B 29% C 26%
at 1.0 27 50 get A 22%, B 32%, C 26% - images look blurry, but this may be due to focusing of camera? or beam-alignment needed?
These voltages are far from the 2021-02-03 values [0.28, 27.0, 48.0]...
B-blur better at 1.0 32 102.5 (A blur 57%, B 77%, C 58%)
C-nubunyn at 1.0 28, scanned 102.5 (A 78%, B blur 64%, C 4.1%)
B-blur is sideways, so change C34cm? at 1.0 28 100.2 get (A 71% ,B 78%, C 46%) all images sharp
C-minimum at 1.0, 25, scanned 100.2 (A 1.9% !, B blur 63%, C 0.3%) first found point that is AC-optimal
B-blur better at 1.0, 25, 98.2 (A 45%, B 77%, C 45%)
C-minimum at 1.0, 22, scanned 98.2 (A 75%, B 63% blurry sideways, C 5.2%)
A-blur reduced at 1.0, 22, 96.2 (A 75%, B 75%, C 36%)
C-contrast minimum at 0.6, 22, scanned 96.2 (A 59% blurry, B 66%, C 1.3 %)
C-contrast minimum at 0.6, 23, scanned 97.4 (A 77%, B 68%, C 3.7%)
A-blur reduced at 0.6, 23, 96.44 (A 75%, B 61%, C 20% )
C-contrast minimum at 0.3543, 23 and scanned 96.44 (A 61,6% blurry vertical image!, B 19.5%, C 4.6%)
C-contrast minimum at 0.3543, 24 and scanned 97.33 (A 75,6%, 19.4 %)
C-contrast minimum at 0.3543, 23.4963 and scanned 96.88
Manually: A: 75%, B: 27%, C: 13% at [0.3306, 23.455, 97.98685]
Further searching gives 0.3, 29, 93 V. This gives reasonably sharp ion image with clear diffraction rings
Here uMotion A 75%, B 77%, C 76% - correlation histograms roughly sine-shaped
Manually found better voltage combination for A and B (harmonic, but high contrast): [0.9, 28, 91]
detuning changes fluorescence very little - indicating lots of uMotion?
detuning back to 208 MHz (from loading value of 185 MHz)
similar blurred image as before - showing blurred diffraction-rings typical of the imaging objective
blocking some beam briefly gives a cooled ion
12:48:05Z signal (axial mode? not cooled?)
12:43:15Z load with 1.7A dispenser
12:40 throw away old ion(s)
lots of uMotion? maybe have 2 ions?
ID11722: Leave NPL umotion search over lunch.
Ion image blurry, lot of micromotion?
Blink test shows only 2 levels, single ion?
Readjust PMT splitter.
try to align all beams, so we get bright fluorescence
422 detuning to 208 MHz
07:44 signal! quite far right from where camera center was aligned?
07:43 load with 1.7A dispenser
align A-beam with help of output diffraction pattern
remove PMT-splitter, align camera to electrodes
07:31Z dispenser off, no clear signal
07:18Z try to load, 1.7A dispenser.
Adjust 461 current.
06:55Z try to load, 1.7A dispenser. No ion after 15 min.
Adjust A-beam position
Cavity drift with minus-K floating now seems better? This day Lunch 12-13 and team-development 13-15 - chronograf figure with local time on X-axis?
need to remove PMT-splitter, to get better image with intensifier?
15:04Z no signal..
intensifier gain 3.77V, PCO camera exposure 222ms
14:53Z try to load, 1.7A dispenser.
install intensifier + PCO-camera
need to install intensifier? to align A-beam?
14:19Z no signal in 14 min.
14:05Z try to load, dispenser 1.7A (1.75W.. rises to 1.815W after 10min)
ASI camera USB-cable pointing vertically down gives horizontal inner-electrode images
with modified imaging-objective (0.5" slimmer lens-tube, to fit outer shield cimney), focus position is ca 1mm back from previous setting
then move in Z 425um up. (upper electrode appears ca 850um up from lower)
focus on lower electrode, then move focus inside 750um/2.
removed also mid and inner shield (camera side) in order to find electrode images
remove outer shield, to align camera to electrodes
no signal in 11mins... check camera alignment to electrodes?
09:00Z try to load, with 1.7A (1.74 W)
RF monitor 2.74 Vpp
A 461nm, 250 uW (fiber was blocking IR-beam, and temp/current adjusted after moving driver-boxes)
422nm A 0.9uW, B and C 1.0 uW, detuning 185 MHz
405nm A adjusted to 3 mW
Check 461 driver settings: T = 4.642 kOhm , I = -195.23 mA (dispenser 5A and ca 2min as usual)
Adjusted 422 input polarization.
Temperature rise with outer top shield installed
14:45Z close cavity-doors after adding 3rd minus-K clamp and aligning laser to cavity
SRS shutter test:
Quiet: 10:06 - 10:19 (STDEV: CH1: 26.4 Hz, CH2: 26.4 Hz), SRS shutter (1 ms probe): 10:21 - 10:34 (STDEV: CH1: 27.4 Hz, CH2: 27.4 Hz).
14:47Z close cavity doors
Clamp down minus-K so it doesn't move
turn off cooling-laser, ASE.
no ion.. Storage time from Monday 25.1 to Friday 4.2, ca 11 days?
try large 422-detuning, and ramping back to 208 MHz
try 461nm laser
try 405nm laser
try to re-lock to Rb-line, but no ion..
Shutter noise tests:
Nothing happens: 15:14 - 15:19
Dummy clock run with 1000 ms probe: 15:20 - 15:25
Ion seems to been lost.
ID11687 NPL uMotion search, 100kPhotons. Result: [ 0.24382725 26.82098208 48.19374483]
ID11686 Peak search with OD2+OD3 based on C4 linecenter and B estimates from clock run. Probe = 190 ms, 2021-02-05-search-1
0.4 Hz sampling, 13 Hz range. 2 Hz expected AOM FWHM.
Switch to OD2+OD3. Try to operate experiment remotely.
10:16Z Abort clock-run
ID11684: Clockrun with OD1+OD3, 60ms probe, based on C1 estimates of linecenter and B field. 2021-02-04_clockrun1
New compared to last clock-run: Continuous drift-compensation with ARTIQ-DDS, adjusted in real-time to 2h drift-estimate from comb data. 2nd-order servo in peak-lock algorithm.
ID11669: OD1+OD3 peak search with probe = 60 ms. 2021-02-04-search18-. Initialized based on C1 linecenter and B from previous measurement.
C1+ 75 965 302.4 Hz, FWHM 5.6 Hz, h33
C1- 75 959 600.5 Hz, FWHM 7.0 Hz, h43
C1center = 75 962 451.4 Hz, B = 1.016029 uT
ID11678: Rabi flopping on C1+ with OD1+OD3. ~60ms still ok.
ID11669: OD1+OD3 peak search with probe = 60 ms. 2021-02-04-search17-. Initialized based on C1 linecenter and B from previous measurement.
C1+ Center visually 75.965301
ID11673: Rabi flopping on C1+ with OD1+OD3. Excitation only ~16% at max.
ID11671: OD2+OD3 peak search with probe = 190 ms. 2021-02-04-search15-. Initialized based on C4 linecenter and B from previous measurement.
Sampling 0.4 Hz, range 12 Hz. Aborted during C2+.
ID11669: OD1+OD3 peak search with probe = 60 ms. 2021-02-04-search14-. Initialized based on C1 linecenter and B from previous measurement.
C1+ 75 965 311.5 Hz, FWHM 7.4 Hz, h30
C1- 75 959 609.5 Hz, FWHM 6.8 Hz, h44
C2+ 75 968 143.3 Hz, FWHM 6.9 Hz, h38
C2- 75 956 774.3 Hz, FWHM 7.9 Hz, h26
C4+ 75 976 676.1 Hz, FWHM 8.4 Hz, h39
C4- 75 948 237.5 Hz, Unreliable fit, noise in the data.
C1center = 75 962 4605.2 Hz, B = 1.016047 uT
ID11667: OD1+OD3 peak search with probe = 60 ms. 2021-02-04-search13-. Initialized based on C1 linecenter and B from previous measurement.
C1+ fit failed. Visually 75.965312
Linecenter 75.9624608364173 MHz.
ID11664: OD1 peak search with probe = 1.9 ms. 2021-02-04-search11-
C1center = 75.96246910765049 uT
B = 1.017961 uT
Abort after C1 pair.
ID11648: OD1 peak search with probe = 1.9 ms. 2021-02-04-search2-
Drift comp seems stabilized.
ID11643, ID11646: NPL searches with wider range. Trying to debug contrast fitting errors.
uMotions: A: 4% in 12s, B: 1% in 10s, C: 8% in 17s
ID11637: Peak search with OD1. Probe 1.9 ms. 2021-02-04-search1-
+C1 75 965 329.2 Hz, FWHM 240 Hz, h31
-C1 75 959 617.7 Hz, FWHM 212 Hz, h56
C1center = 75 962 473.5 Hz, B = 1.0177363 uT
B-field estimate from the day before (1.018202) seems good enough to predict transition frequencies for OD1.
Adjust comb f0 lock. Restart drift-comp.
07:02Z Abort remaining runs. Drift-comp stopped working 2020-02-03 14:20Z.
leave OD5, 190ms scan over night... may or may not find something?
clock-laser was unlocked for some time at the start of C1+ scan. from pt 33/1000 onward it should be ok
Go to OD3 and 20ms, to find lost peaks..
4 Hz step, 200 Hz span, 51 pts/peak
C1 fit fails... left in the 200Hz span - can we have this much drift?
scan around 75 965 498, to find C1+?
find only low-height peak, try rabiflop there? get only low counts, so we are off-resoncance?
ID11627 Try instead peak-search with OD4 and 60ms probe
C1+ far left in span, maybe 75 965 498 ?
C1- also left? 75 959 780 or lower?
(B seems to have decreased? moves C1+ left and C1- right?)
190ms scan is possible only with well-compensated cavity-drift!
ID11619 repeat OD5, 190ms peak-search (search9)
Reset estimates based on C4 linecenter and B-field from OD1+OD3 peak search.
Estimate tau_pi = 190 ms with OD2+OD3
ID11618 Peak search with OD2+OD3, 190 ms probe 2021-02-03-search8-.
Sampling 0.4 Hz, range 12 Hz.
+C1 75 965 513.20 Hz, FWHM 2.2 Hz, h26
-C1 75 959 798.60 Hz, FWHM 2.1 Hz, h41
C2 fit failed. Visually: 75 968 350.4 h37
C1center = 75 962 655.90 Hz, B = 1.018282389 uT
ID11613: Rabi-flopping on C1+ OD1+OD3. tau_pi ~60 ms seems ok.
Reset B-bield and linecenter estimates based on previous C1 peak search.
ID11612 Peak search with OD1+OD3, 60 ms probe 2021-02-03-search6-.
+C1 75 965 513.9 Hz, FWHM 6.5 Hz, h32
-C1 75 959 799.2 Hz, FWHM 7.1 Hz, h41
+C2 75 968 352.7 Hz, FWHM 7.0 Hz, h34
-C2 75 956 959.5 Hz, FWHM 7.4 Hz, h29
+C4 75 976 905.5 Hz, FWHM 7.2 Hz, h36
-C4 75 948 404.0 Hz, FWHM 7.5 Hz, h
C1center = 75 962 656.6 Hz, B = 1.0182969 uT
C4center = 75 962 654.8 Hz, B = 1.0182016 uT
ID11610 Peak search with OD1+OD3, 60 ms probe 2021-02-03-search5-. Aborted after C1 pair.
+C1 75 965 513.6 Hz, FWHM 7.5 Hz, h33
-C1 75 959 798.8 Hz, FWHM 7.0 Hz, h38
C1center 75 962 656.2 Hz, B1 = 1.0183112 uT
ID11607 Peak search with OD1, 1.9 ms probe 2021-02-03-search3-.
+C1 75 965 505.5 Hz, FWHM 196 Hz, h42
-C1 75 965 505.5 Hz, FWHM 228 Hz, h49
C1center 75 962 650.3 Hz, B1 = 1.0175206 uT
uMotions at new 'optimum': A: 2.5% in 11s, B: 1% in 10s, C: 7.7% in 15s
ID11959: NPL search again. Optimum out of bounds again. Selected manually: [0.28, 27.0, 48.0]
ID11594: NPL uMotion search around new 'optimum'.
uMotions at new 'optimum': A: 6.5% in 10s, B: 7.2% in 10s, C: 3.1% in 14s
ID11589: NPL uMotion search. Optimum out of bounds. Manually selecting: [0.29, 26.6667, 48]
uMotions: A: 7.4% in 11s, B: 24.5% in 10s, C:22.0% in 15s
06:50Z Stop clock run.
ID11583 try to start OD4, 60ms clock-run
Cycle duration is ca 133 seconds. This should roughly match 6 peaks * 2 R/B sides * 100 shots * (100ms probe + 40 ms dead) = 120 s (check what our actual programmed dead-time is?)
For clock-run results see ion.
ID11578 peak-search, OD4, 60 ms (Fourier limit 6.7 Hz AOM)
1.3 Hz step, 30 Hz span, 23 pts/peak
+C1 75 965 645.2 Hz, FWHM 7.4 Hz, h29
-C1 75 959 936.7 Hz, FWHM 7.1 Hz, h39 (right in span)
C1center 75 962 790.9 Hz, B1 = 1.017194 uT
initialize clock-run with these values. (initializing with a C4 peak search might be better? more accurate abs(B) value)
ID11577 peak-search, OD3, 19 ms
2.5 Hz step, 50 Hz span, 21pts/peak
50/100Hz sidebands not resoled? this is not a good probe length?
ID11576 peak-search, OD1, 1.9 ms
now better peak-height with correct tau_pi
+C1 75 965 647, FWHM 202 Hz AOM, h38
-C1 75 959 931, 208Hz, h49
C1center 75 962 789, B1 = 1.0185 uT
+C2 75 968 488, 227 Hz, h44
-C2 75 957 102, 229 Hz, h34
+C4 75 977 030, 221 Hz, h47
-C4 75 948 563, 229 Hz, h27
OD1 rabiflop on center gives 1.9ms tau_pi.
674nm power in A-beam seems reduced? re-align?
ID11569 peak search, OD1 and 3ms - but get low peak-height for +C1, so probe length is wrong?
ID11568 rabiflop on +C1 (75 965 644), with OD3,
ID11567 peak search, A-beam, OD3, 30ms probe
2.5 Hz step, 100Hz span, 41pts/peak
ion dark moment? abort
ID11563 peak search, A-beam, OD3, 30ms probe
uMotion at old voltages 100kphot: A 7.3%, B 19%, C 13%
ID11557: OD1 peak search with adaptive Artiq drift comp. 3 ms probe, 2021-02-02-search4-
uMotions: A: 6% in 13s, B: 22% in 10s, C: 18% in 15s
ion still stored (now 8 days?)
Leave 100ms peak-search over night. 0.8 Hz step, 200Hz span, 251 pts/peak
A-beam, 18 dB Zatt., OD4, 100ms probe
Quite difficult to get a clock-run to lock to the peaks with so much uncompensated cavity-drift...
100ms peak search again. 0.8Hz step 20Hz span
f_beat_center = 75 962 869
+C1 far left in span ?
Try clockrun initialized with (centers, FWHMs AOM, gains) [75.96589229 75.95992971 75.96885552 75.95696648 75.97778133 75.94804067] [4.e-06 4.e-06 4.e-06 4.e-06 4.e-06 4.e-06] [0.5 0.5 0.5 0.5 0.5 0.5]
100ms probe, 6 peaks gives cycle time of ca 181 s
somehow we again have +10 mHz/s of uncompensated cavity drift. This gives 1.8 Hz @ 674nm drift during the 180s servo-cycle. For a 100ms probe, 8 Hz Fourier limit, this is 1/4th of the FWHM!
ID11534 peak search with 100ms
+C1 far left in span? 75 965 892 (or even lower?)
-C1 right in span 75 959 929
C1 center 75 962 911 and B1 1.06247 uT
predicted line-center from beat-note 75 962 884
Try clock-run with 100ms probe, but servos seem not to find the peaks..
Based on OD3 results, switch to OD4 and 100ms probe.
ID11528 peak search A-beam, 18 dB Zatt, OD4, 100ms probe, 0.8 Hz step, 20 Hz span, 25 pts/peak
+C1 seems far left in the span? 75 965 901
-C1 more centered in span (why?),and higher, 75 959 922
C1center 75 962 912 and B1 1.06532 uT
With OD3 and 30ms, found C1 peaks:
+C1 at 75 965 910
-C1 at 75 959 920
C1center 75 962 915 and B1 1.0673 uT
ID11525 A-beam peak search. 18 dB AOM att, OD3-filter, 30ms probe
2 Hz step, 200 Hz span. 101 pts/peak
C beam 106/3 counts in 10ms
B beam 94/3 counts in 10ms
A beam fluorescence 173/4 bright/dark counts in 10ms
422 power A 1.5uW, B 1.9uW, C 1.5 uW
13:05 after many hours of working with the 422-laser (no cooling), ion re-appeared!
repeat measurement of the cavity power-shift (Friday result was 190Hz/V @ 1348 nm)
With reduced FALC-gain, photodiode signal is slightly more than before.
Cavity drift-compensation should also match true cavity drift better than before
13:45Z set-point 0.8 V, 5min beat-note 23 164 432.26 (stdev 30.39 Hz)
13:52 set-point 0.7V (BOA 430 mA), 5 min beat-note 23 164 433.33 (valid data only)
14:01 set-point 0.8V (BOA 480 mA), 5 min beat-note 23 164 434.19 (31.19 Hz) - not much evidence of power-shift?
14:24 set-point 0.9V (BOA 520 mA), 5 min beat-note 23 164 434.41 (32.57 Hz)
14:56 set-point 1.0V (BOA 580 mA), 5 min beat-note (this hits the BOA current limit of 600 mA)
again dark image after power-measurements? takes a long time to cool and get an image?
422nm 0.6uW in A-beam
15-20 uW before ABC-beamsplitter
A-beam fluorescence 32/12 bright/dark in 10ms gate. B and C weaker
09:47Z ion re-appeared!? maybe weaker image than before, lower 422nm power after fiber-adjustments
09:40Z seems we lost the ion?, while adjusting polarization (no cooling-laser)
422nm Polarization extinction ratio improved from 7 dB to 10 dB, on ion-breadboard after 422-laser-fiber, before ABC-beamsplitter
Note on cavity doors closed (Friday):
Coarse heater-power dropped from 90W to 30W - as before. time-constant is 'fast', below one day
Inner shield free-running temperature sensor seems to settle at to a temperature +4...6 mK than before. Very slow settling, maybe a week?
09:24Z adjust comb f0-beat SNR to >25 dB
Updated drift-comp to current observed value of 12.6 mHz/s
Reducing FALC-gain (trimpot) gives lower servo-bump sidebands and more power transmitted through cavity, now 0.85 V
'Heating' fiber by hand, both laser -> breadboard and breadboard -> ion.
ID11492: A-beam, samples: 0-200: laser-> breadboard, samples: 200-350 breadboard->ion, 350 ->: laser to breadboard. Changes mostly in first case.
ID11490: C-beam, samples: 0-200: laser-> breadboard, samples: 200-350 breadboard->ion, 350 ->: laser to breadboard. Changes in both cases.
ID11488: B-beam, samples: 0-200: laser-> breadboard, samples: 200-350 breadboard->ion, 350 ->: laser to breadboard. Changes in both cases.
ID11486: A-beam, PMT count changes with heating laser -> breadboard, but not with breadboard -> laser.
Check 422 beam polarizations.
Cancelled long experiment from ID11481 forwards.
Leave B-beam, OD5, 60 ms peak search over night
Maybe 50/100 Hz sidebands are smaller, when t_probe is a multiple of 10 or 20 ms?
ID11477 (narrow span), 11478(search5), 11479(6), 11480(7) (aborted), 11481(8) (cancelled), 11482(9) (cancelled), 11483 (10)(cancelled)
Try B-beam instead?
rabiflop with OD3 suggest maybe 10ms tau_pi?
peak-search with 10ms and OD3
OD2 tau_pi looks like 3ms
OD3 maybe 10 ms
OD4 no clear oscillation?
OD5 rise tp 60ms, then flatish
recalculate peak-positions based on beat-note and latest B1-estimate.
try peak-search with OD1 and 100ms probe
+C1 at 75 965 640. try rabiflop there.
no clear signal, try OD3 and 30ms instead.
ID11467 peak-search with OD3 and 30ms
rabiflop on 75 965 669, with OD3. no higher than 25 counts?
abort long run.
ID11461 OD3+OD2 and 290ms peak search, long, over night. 290ms is a guess of tau_pi, might be too long?
18dB Zeeman AOM atteunation.
0.3 Hz step, 150 Hz span, 501 pts/peak
duration ca 30s per point = 4 hours per zeeman peak! done in ca 24 hours..
Fourier limit 2.8Hz optical, 1.4 Hz AOM. ca 5 steps of 0.3 Hz AOM each
ID11460 peak search with OD3 and 29ms probe
49pts/peak. 150 Hz span, 3 Hz step
Fourier limit is ca 25 Hz - so the 50/100 Hz sidebands are resolved.
ID11458 peak search with OD1 and 2.9ms probe
+C1 75 965 242, FWHM 174, h26
-C1 75 959 314. FWH; 153, h34
C1center 75 962 279, B1 1.0562 uT
+C2 75 968 195, FWHM 159, h35
-C2 75 956 362, FWHM 169, h31
+C4 75 977 060, FWHM 152, h27
-C4 75 947 479, FWHM 149, h18
Estimated line-center from comb 75 962 255
here get: A 6.7%, B 13.3%, C 8.4 %
algorithm suggests [ 0.27459138 26.48031258 49.01349212]
old voltages: 0.2693, 26.9714, 49.4475.
ID11446 Try short uMotion-search 3x3x3 grid with 30kphotons
uMotion 100kphot: A 15.3%, B 14.7%, C 9.6%
15:56Z stop collition monitor
cavity output-power now more than on Friday? ca 0.7 V
comb f0 lock seems very unstable
fiber was blocking ion-breadboard 674nm power-detector...
turn on comb, comb-branch, clock laser
15:50Z ion still stored
16:27Z leave lab.
16:20Z start collision-monitor with 10ms gate, 65/3 bright/dark. DB tag '2021-01-29-run1'. NO clearout.
Fluorescence levels 66 / 2.8 in 10ms
Switch to B-beam.
Turn off clock-laser and beat-note branch
Comb f0 unlocked. (maybe lab-temperature changes when cavity-box was closed?)
Cavity drifts too much to leave any useful clock-laser runs
ID11439 re-start OD3/29ms search, with wider span, since we have so much uncompensated cavity-drift.
ID11438 peak search with OD3 and 29ms probe (Fourier limit 13 Hz AOM)
Note we have 50-60 mHz/s uncompensated cavity drift!
C1 Gaussian fit fails...
ID11437 repeat peak-search (since something jumped??)
Cavity drift seems to be 70 mHz/s - since we touched the cavity when testing power-shift
C1 75 964 506, FWHM 97 Hz, h24 and 75 958 555, FWHM 107Hz, h36
C1center 75 958 555, B1 1.0604 uT
C2 75 967 440, FWHM 107 Hz, h38 and 75 955 605, FWHM 123 Hz, h21
C4 75 976 334, FWHM 94 Hz, h32 and 75 946 679, FWHM 89 Hz, h21
ID11436 peak search, OD2, 9.9ms probe (Fourier limit 40 Hz AOM). 8 Hz step, 170 Hz span
C1 75 964 528, FWHM 93 Hz, h21 and 75 958 587, FWHM 103 Hz, h31
C1center 75 961 557, B1 1.0587 uT
C2 75 967 452 FWHM 112 Hz, h32, and jump??
C4 only zeros?
ID11435 Repeat OD1 peak search for C1 pair. 3.3ms probe (Fourier limit 121 Hz AOM), 25 Hz step
C1 FWHMs 134 Hz and 150 Hz
C2 FWHMs 150 Hz and 164 Hz
C4 FWHMs 133 Hz and 137 Hz
(measurement time 688s)
ID11422: Rabi flop with OD1, att. 18 dB. tau_pi 3.3 ms. -> use 10 ms for OD2
ID11418 Line scan over C1+ with 18 dB att. and OD1.
ID11415 Rabi flopping on C1+ with 18 db att. and OD1. Measurement was off-peak.
ID11411 peak-search with OD1 and 3ms probe. 15 dB att. C4+ fit wrong. Corrected dataset manually.
13:08 close cavity doors
Try to measure cavity power-shift.
ca12:20Z: 0.40 V power-servo set-point (servo measures cavity output-power with photodiode, and steers BOA 1348nm amplifier current)
12:24 feedback off
12:24:30 0.3V set-point, feedback ON
1s comb-data noise is ca 25 Hz at IR frequency of 222.5 THz (1e-13, the maser noise level at 1s)
5min = 300s average should give 1/sqrt(300) of this, or 1.4 Hz @ IR = 2.2e-14
12:32 adjust power-servo, set-point 0.4V (servo on causes BOA current variations 450-490 mA)
5min beat-note 23 161 465.41 (1s stdev 25.8)
12:37 servo off
12:39 servo set-point 0.3V (BOA current 350-380 mA) - servo-bumps on beat-note SA look much smaller
5min beat-note 23 161 492.17 (1s stdev 27.2)
12:44 servo off
12:46 set-point 0.35V (BOA current 410-440 mA)
5min beat 23 161 508.94 (1s noise 25 Hz)
12:52 set-point 0.45V (490-530mA)
in-loop photiode scope-signal at mu=451, 450.9, 451.0, 451.0, 450.9, 451.0, 451.2 451.1 451.0 451.1 mV
5 min beat 23 161 522.1 (25.3 stdev)
Power-shift slope is 190 Hz / V of frequency shift in IR, relative to cavity-output photodetector voltage
This is 8.5e-13 fractional per volt.
If we want a 1 Hz 674nm laser-stability, we need 0.5 Hz in IR, or 2e-15 fractionally
This leads to a requirement of 2.6e-3 for the fractional voltage stability of the photodetector
Closed-loop we see 0.3mV/450mV which is 7e-4 fractional
uMotion contrasts with new voltages [ 0.26927269 26.97143157 49.44745276]: A: 2% in 11 s, B: 5% in 12 s, C: 2% in 17 s
ID11403: NPL search for umotion minimum: 4x4x4. Result: [ 0.26927269 26.97143157 49.44745276] (optimum now within search-grid?)
-0.0203 2.7627 2.2088
0.3076 -1.4601 0.2457
0.2695 1.1614 -3.8900
Previous voltages: (0.3821,26.7839,51.0685)
ID11400: NPL search for umotion minimum: 4x4x4. Result: [ 0.22398756 27.24888464 49.35180688]
uMotion 100kphot: A 30% in 10s, B 46% in 11s, C 23% in 13s
Peak search terminated (ID11392). Partial +C1 data in DB.
(rabi-sinc with transform-limited FWHM shown for reference)
ID11391, ID11392: Overnight: Peak search with OD2+OD3 filter, 225 ms probe
DB-tag: 2021-01-28-search14-, -search15-.
Fast drift comp. Estimated length of one search: 2.2 hrs per peak = ~13 Hr
100 Hz span per peak. Step: 0.3 Hz, 333 pts/peak. Fourier limit 1.78 Hz AOM
ID11387, ID11388: Rabi flop with OD1+OD3. tau_pi closer to 75 ms. -> use 225 ms probe for OD2+OD3.
ID11386: Scan over +C1 with OD1+OD3 filters, 72 ms probe, DB-tag: 2021-01-28-run8. With fast drift-comp.
ID11385: Peak search with OD1 filter, 3 ms probe, DB-tag: 2021-01-28-search12-. Fast drift comp.
+C1: height 28, FWHM: 173 Hz
-C1: height 42, FWHM: 178 Hz
+C2: height 42, FWHM: 172 Hz
-C2: height 27, FWHM: 147 Hz
+C4: height 53, FWHM: 152 Hz
-C4: height 30, FWHM: 163 Hz
ID11382: Scan over +C1 with OD2+OD3 filters, 216 ms probe, DB-tag: 2021-01-28-run7. With fast drift-comp.
ID11381: Scan over +C1 with OD1+OD3 filters, 72 ms probe, DB-tag: 2021-01-28-run6. With fast drift-comp.
Disable drift-comp in crontab, and update drift-DDS every second:
ID11378: Scan over +C1 with OD1+OD3 filters, 72 ms probe, DB-tag: 2021-01-28-run4. With fast drift-comp.
ID11377: Scan over +C1 with OD1+OD3 filters, 72 ms probe, DB-tag: 2021-01-28-run3. With normal drift-comp.
ID11376: Scan over +C1 with OD1+OD3 filters, 72 ms probe, DB-tag: 2021-01-28-run2. With normal drift-comp.
ID11375: Scan over +C1 with OD2+OD3 filters, 216 ms probe, DB-tag: 2021-01-28-run1
ID11373: Peak search with OD1+OD3 filters, 80 ms probe, DB-tag: 2021-01-28-search9-. Aborted after C1-
ID11372: Peak search with OD1 filter, 3 ms probe, DB-tag: 2021-01-28-search8-. Data looks OK now.
+C1: height 34, FWHM: 151 Hz
-C1: height 47, FWHM: 162 Hz
+C2: height 44, FWHM: 164 Hz
-C2: height 27, FWHM: 151 Hz
+C4: height 44, FWHM: 160 Hz
-C4: height 26, FWHM: 170 Hz
Switch back to A-beam
It turns out, that C-beam was on?!?!
ID11363: Rabi flopping without OD filters
ID11351: Peak search with OD1, peaks seems really broad.
re-lock comb f0
uMotion 100kphot: A 18.2% in 10s, B 38% in 9s, C 9% in 18s
08:40Z ion still stored. Clock-laser locked. Comb f0 unlocked sometime during the night
60s stack of 1s exposures. old objective, ASI camera
ID11337 (run4), 11338 (run5), (18 local)
ID11339, 11340 (19 local)
ID11341, 11342 (20 local)
ID11343 (21 local)
ID11344, 11345 (22 local)
ID11346 (run13), ca 23 local?
OD3+OD1 filters, guess 72ms tau_pi (Fourier limit 5.6 Hz AOM). scan C1+ many times. 400 Hz span, 1Hz step
each scan takes 4900 seconds = 1.4 hours
10 scans in the queue, run3 thru run13
ID11322 peak-search with OD2 and 7.2ms probe (Fourier limit 56 Hz AOM). 400Hz span, 10Hz step, 41 pts/peak
C1+ h 24, FWHM 109 Hz
C1- h 38, FWHM 99 Hz
B1 1.0585 uT, linecenter 75 962 451
C4+ h 32
C4- h 18
Try OD2 filter.
ID11319 rabiflop on +C1, tau_pi 7.2 ms?
ID11315 rabiflop on +C1.
ID11314 peak search with OD3, 20ms probe (guess of tau_pi), Fourier limit 20 Hz AOM, 200 Hz span, 5 Hz step, 41 pts/peak
+C1 75 965 411, h 13, FWHM 89 Hz but Gaussian fit does not fit central peak
-C1 75 959 471, h 21, FWHM 76 Hz. Central peak ca 25 Hz AOM wide
B1 1.058 uT
linecenter 75 962 441 Hz
C2+ 75 968 369, h 22, FWHM 96 Hz
C2- 75 956 527, h 18, FWHM 79 Hz
C4+ peak is far left in the span, B-field estimate too high?
C4- peak is far right in span
Repeat OD1 search (ID11313), Influx tag: 2021-01-27-search6-
all peaks roughly transform-limited with 3 ms probe
Rerunning peak search with OD1 (ID11312), probe 3 ms, Fourier limit 133 Hz AOM, Influx tag: 2021-01-27-search6-:
C1+ heigth 33 FWHM 154 Hz
C1- height 40 FWHM 166 Hz
C2+ height 34 FWHM 191 Hz
C2- height 24 FWHM 166 Hz
C4+ height 49 FWHM 155 Hz
C4- height 29 FWHM 152 Hz
Problem with saving Zeeman-peak data in peak-search program. Problem corrected.
Try OD3 filter, should work with 27ms?
ID11286 peak search, A-beam, OD3 filter, 27ms probe. Fourier limit 15 Hz AOM. 150 Hz span, 3 Hz step, 49 pts/peak
(db tag 2021-01-27-search5-)
+C1 central peak looks OKish, but Gaussian fit is to all of data. no clear 100Hz sidebands?
Other peaks looks similar
Clock probe maybe too long?
Try OD2 filter, should work with 9 ms probe
ID11285 peak search, A-beam, OD2 filter, 9ms probe (Fourier limit 44 Hz AOM). 250 Hz span, 10 Hz step, 25 pts/peak
(Note Fourier limit close to AC frequency of 50Hz - could interfere?)
(db tag 2021-01-27-search4-)
+C1 h 22, FWHM 136 Hz AOM - looks noisy, Gaussian not a great fit (span is a bit narrow)
-C1 h 34, FWHM 115 Hz - B1 1.065 uT - linecenter 75 962 441 Hz
+C2 h 33, FWHM 140 Hz - strong sidebands at 5 steps = 50 Hz AOM = 100 Hz optical from center! - Gaussian is fit to everything, not only central peak
-C2 h 21, FWHM 153 Hz - also sidebands
+C4 h 37, FWHM 104 Hz - highest peak in this run! - not any wider than C1/2, so isn't limited by B-field?
-C4 h 79, FWHM 110 Hz - Gaussian covers central peak and side-bands..
Try OD1 filter, this should work with 3ms probe
ID11283 (data file stored as ID11284?) peak search, A-beam, OD1 filter, 3ms probe (Fourier limit 133 Hz AOM). 500 Hz span, 25 Hz step, 21 pts/peak
(db tag 2021-01-27-search3-)
+C1 h 33, FWHM 157 Hz AOM
-C1 h 46, FWHM 157 Hz - B1 1.066 uT - linecenter 75 962 434 Hz
+C2 h 45, FWHM 142 Hz
-C2 h 25, FWHM 175 Hz
+C4 h 45, FWHM 164 Hz
-C4 h 26, FWHM 183 Hz
ID11275 NPL uMotion search over lunch. 4x4x4 grid
algorithm suggests Optimal voltages (Common mode, diff): [ 0.38212489 26.78389499 51.06850713] - both first and last value are outside scan range.
Try suggested voltages.
uMotion 100kphot: A 4.7% in 14s, B 27.3% in 12s, C 12.9% in 14s. (overall better than before, but not optimal)
ID11274 peak-search with 1000us probe (Fourier limit 400 Hz AOM). 1.5kHz span, 80 Hz step, 19 pts/peak
+C1 height 43, FWHM 384 Hz
-C1 h 52, FWHM 423 Hz - B1 1.064 uT - liencenter 75 962 455 Hz
+C2 h 50, FWHM 405 Hz
-C2 h 41, FWHM 356 Hz
+C4 h 51, FWHM 432 Hz
-C4 h 30. FWHM 415 Hz
(duration 607 seconds)
ID11272 rabilfop on +C1, to 5 ms probe. tau_pi ~ 1ms (this might give better peak-heights than previous peak-search)
ID11271 rabiflop on +C1
Peak search (ID11270, 18 dB att., 500 us probe):
+C1: Center = 75.9654 MHz, height 20, FWHM: 890 Hz.
-C1: Center = 75.9594 MHz, height 27, FWHM: 942 Hz.
+C2: Center = 75.9684 MHz, height 35, FWHM: 873 Hz.
-C2: Center = 75.9565 MHz, height 22, FWHM: 861 Hz.
+C4: Center = 75.9773 MHz, height 22, FWHM: 862 Hz.
-C4: Center = 75.9476 MHz, height 12, FWHM: 840 Hz.
B estimate = 1.07137 uT.
Coil currents set to (-8,0,0).
-3 floor A/C setting is 20 Hz
NOTE uMotion contrasts not optimal, all beams ca 30% now!
ID11260 compare to non-zero B-filed by flipping I1 sign, currents: (+4.4719, -1.0115, 1.0309) mA. lower 18 kcounts/s at max
ID11258 repeat A-beam detuning scan, 1000ms gate. Far detuned 2 kcounts/s, near resonance max 21.3 kcounts/s
ID11257 A-beam detuning scan - no Dork-resonances apparent..
ID11254 clock-spectrum with zero B-field, 500us probe (Fourier limit 800 Hz AOM), 3 kHz span, 50Hz step
Gaussian fit FWHM 908 Hz
center 75 962 438
ID11252 rabiflop on center, in zero B-field, visually tau_pi ca 500us
ID11248 clock-spectrum with zero B-field?
A-beam, 600us probe (Fourier limit 667 Hz AOM), 100Hz step, 5 kHz range. zeeman AOM attenuation 18dB from y-day
Gaussian fit FWHM 760 Hz AOM
center 75 962 481 Hz
Try the zero B-field currents I1 = -4.4719, I2 = -1.0115, I3 = 1.0309
uMotion 100kphot: A 36.3% in 9s, 30.4% in 10s, 28.7% in 13s
08:19Z ion still stored, clock-laser locked to cavity, but comb f0 was unlocked.
Initial coil results:
B = B0 + A I
0.2649(2) 0 0
0 0.41962(14) 0
0 0 0.2713(2)
% current giving zero field
IO = [-4.4719 -1.0115 1.0309] mA
A-beam, 600us probe, 500Hz step (note this is quite sparse sampling... Fourier limit 667 Hz AOM), 50 kHz span, 101 points per spectrum
ca 5s per point, so only 500s per spectrum. We have 3*6 spectra, so 3*6*500 = done in 3 hours.
step each current: +2, -2, +4, -4, +8, -8 mA.
2021-01-26-coil-0-0-0 is the first run, with zero currents
0, 0, 0
+2, 0, 0
-2, 0, 0
+4, 0, 0 leave lab around 17:10 local, artiq got to this point.
-4, 0, 0
+8, 0, 0
-8, 0, 0
0, +2, 0
0, -2, 0
0, +4, 0
0, -4, 0
0, +8, 0
0, -8, 0
0, 0, +2
0, 0, -2
0, 0, +4
0, 0, -4
0, 0, +8
0, 0, -8
Note the last coil characterization results from 2020-08-19: (coil sensitivities very similar on 2020-06-12)
A2 = [0.216895938211581 0 0;
0 0.325633046718816 0;
0 0 0.208504965524669];
B02 = [1.085916150083249, 1.291554002640864, -0.100996485194311]';
orange: zero coils
blue: I1 varied
red: I2 varied
green: I3 varied
Remove OD-filters, for overninght coil characterization
A-beam, no OD filters, rabiflop shows 600us tau_pi
Spectrum with 4.5ms and 18dB attenuation. Fourier limit 89 Hz AOM
Gaussian fit FWHM 124 Hz AOM
center 75 963 825 Hz
Try increasing Zeeman AOM attenuation, to only slightly lower probe intensity. Attenuation 18dB.
Rabi-flop on center gives 4.5ms tau_pi
ID11197 scan with OD2 and 3.2ms. Fourier limit 125 Hz AOM
Gaussian fit FWHM 144 Hz AOM
Center 75 963 826
ID11195 rabiflop on center, OD2 filter. tau_pi 3.2ms
OD3 filter is too hard? go back and try OD2 filter?
re-run rabiflop on center
re-run +C1 scan with 9400us probe (Fourier limit 42 Hz AOM). A-beam, OD3 filter
Gaussian fit FWHM 102 Hz AOM
Rabiflop, to find tau_pi?
OD3 filter, 15ms probe, scan around +C1
OD2 filter, 4500us probe, scan around +C1
Try coil currents (-4, 0, 0) mA, scan with 450us
Peak-search with A-beam and 450us probe:
but doesn't find C1.
rabiflop on -C1, visually tau_pi ca 450 us
P674_A = 0.8 uW, no OD-filters (note B-beam had about 5uW!)
Try A-beam, it may have better 422nm polarization?
ID11174 scan with 600us probe pulse
C1 peak search OD3+OD1 filter, 15 ms probe, 5 Hz step, 100 Hz span, Fourier limit 27 Hz AOM
+C1 not a great peak..
-C1 75.960007, FWHM 70 Hz AOM, h 22 (Gaussian fit not so great)
C1 peak search, OD3 filter, 5400us probe pulse, 300 Hz span, 20 Hz step, Fourier limit 74 Hz AOM
+C1 75.964675, 129 Hz, h 19
-C1 75.960007, 124 Hz, h 35
B1 = 0.832 uT
C1 peak search, OD2 filter, 1800us probe pulse, 500 Hz span, 50 Hz step. Fourier limit 222 Hz AOM
+C1 75.964672, 272 Hz, h 19
-C1 75,962336, 246 Hz, h 48
B1 = 0.832 uT
C1 peak search
+C1 75.964650, 703 Hz AOM FWHM, height 30
-C1 75.962345, 753 Hz FWHM, height 32
B1 0.821 uT
Coil sensitivity roughly dB/dI1 = 0.24 uT/mA ?? (compare to previous results)
abs(B0) field at zero coil currents 1.3 uT?
Lineshape scan, OD1: ID11132
Change coil currents to (-2,0,0)
Lineshape scan, OD1: ID11130. C2 peaks (?): 75.97232, 75.95232
Change coil currents to (2,0,0).
Install the OD1 filter, this should increase tau_pi 3-fold, to 600us.
ID11121 scan spectrum with OD1 filter, 600us probe, 40 kHz range, 200 Hz step. Duration 800s
Comb f0 had unlocked over lunch, fixed by adjusting waveplates in GUI
All peaks seem to fit within 40 kHz AOM
ID11120 wider spectrum scan with 200us probe
C1 separation looks like roughly 15 kHz AOM ?
ID11119 rabiflop on +C1(?), tau_pi ca 200us
ID11118 initial clock transition scan with 15dB AOM attenuation, 600us probe pulse.
674 power in B-beam: 5 uW
Detuning scans: A: ID11108, B: ID11110 C: ID11112. Gate 20 ms. Counts: ID11115 (dark approx. 10)
Manually trying: (0.28, 27.3333, 53.3333): 8%, 6%, 3%
Automatic NPL search (ID11098) gave weird result [ 0.08607781 32.11213181 52.31081692]
Try (0.3571, 26.8571, 53.5714), got 3%, 31%, 3%
-0.05B step to (0.1334, 26.77556, 54.59336) gives (3%, 2%, 39%)
Repeating search with (0.2489, 26.6999, 54.6666) gives now 7%, 25%, 29% (repeat 10%, 29%, 36%)
NPL search finished with [ 0.33088186 27.33750859 54.74849937], but ion seems to have disappeared during the night.
Last measured contrast seems ok.
Ion reappeared after switching on all beams.
Contrast with new voltages: 33%, 32%, 16%
Leave NPL-algorithm running, 8x8x8 grid
By scanning V34diff, found B and C optimal point:
Contrasts: 30 1.4 3.9 %
Voltages: 0.2489, 26.6999, 54.6666
Found rough optimum for B beam, by stepping along the B-vector
Contrasts: 71, 13, 69 % at voltage of (0.841, 26.692, 47.1523)
From 2020-10-05 we have some notes on the cardinal directions:
0.2372 2.3100 1.9737
0.4131 -1.5132 -0.0264
0.6644 1.4648 -3.8875
uMotion 100kphot: A 70% in 10s (B and C similar ca 70%)
Coil currents from December were (127.7, 6.1, 18.4) mA. Now set them all to zero
Adjust alignment into 844nm amplifier - seems to improve 422nm power
422nm power seems halved compared to start of day - fiber coupler between 422-laser and ion-breadboard?
uMotion 100kphot: A 73% in 58s
Install mid shield
Install inner shield
Install pt100 sensor on IR side window flange
uMotion 100kphot: A 82 % (anharmonic) in 38s, B 73% in 56s, C 76% in 75s (Note no shields!)
C ca 70 counts/50ms
B ca 100 counts/50ms
A-beam and ASE alignment optimization gives ca 140 counts in 50 ms
Found PMT signal, in upper left corner of camera image, as before.
ion is still stored, Z-focus of camera was wrong..
Align PMT-splitter with help of 422-fiber-end placed at PMT position. This allows aligning the PMT-splitter so 422nm-light is bright at analog camera on IR side
Lost ion (?) while swapping cameras etc.
Install the PMT-splitter next
Switch to the ASI camera. Remove intensifier/PCO.
Align B-beam (thru-transmitted diffraction pattern) -> get fluorescence (slightly weaker) with only B also.
Align C-beam -> we get fluorescence with only C now also.
Try camera (z) focusing - but it was already quite optimal. (thus aligning the camera to the electrodes, and defocusing by 750um/2 is a good way to z-focus the camera)
set detuning to 208 MHz - more fluorescence
optimize A and ASE directions, but no major fluorescence changes. PCO camera to 200ms exposure
11:53:15 see single(?) ion? load time 5min 15s
11:48 try to load single ion. 1.7A dispenser
throw away cloud by shutting off RF
A cooling shows cloud, B and C quite dark (do not cool much?)
11:43:37 dispenser off. cloud remains
11:42 see a cloud! (intensifier gain higher, PCO exposure up to 1.2 seconds). A-beam adjustments while dispenser on finally revealed the cloud.
stopping down the imaging objective with the iris reduces a vertical strange 422-reflection in the camera image
11:27:15Z try load, dispenser 1.7A. Intensifier gain 2.7V, PCO camera 200ms exposure
Align ASE beam with the analog camera, A-beam with the thru-transmitted diffraction pattern from the electrodes.
Optical power in the beams:
422nm A 0.9 uW, B 1.1uW, C 1 uW. 185 MHz detuning
461nm A 180 uW
clearout 65 uW
repumper 10.8 mW
405nm A 3.6 mW
RF 14.424 MHz, 10Vpp generator, 2.759 Vpp monitor (scope in averaging mode)
Latest bias-voltages are from 2020-10-29 (?). They are -6.2, 0.2635, 27.0703, 46.7861. Apply these.
This gives individual voltages: V1 = -6.4635, V2 = -5.9365000000000006, V3 = -19.715799999999998, V4 = 73.8564
Analog camera images IR/ASE side. Intensifier + PCO images ion.
Remove mid top-shield, and inner shields - to allow aligning beams. Mid bottom-shield(s) need not be removed?
Try to trap again?
Temperature rise with thermal compound between helical-resonator and alu-mount.
Adding thermal compound changed helres heating from 120 mK to 90 mK.
Installed longer antenna: monitor voltage now 2.78Vpp! f = 14.422 MHz
re-tune SWR close to 1.0. Monitor 60 mVpp with 10Vpp drive from siggen
Install heatsink-compound between helical-resonator and alu-mount
Install inner and mid-shields. Seems to fit OK. Beams go through shield-holes OK.
Note back feet of mid-shield bottom left/right half did not fit the designed M3 holes - they loose between bottom shields and pump-chamber
Tickler voltages measured after coupling capacitor (at eletrode) with 10x probe. Voltages are peak-to-peak
Measured voltages seem low. Capacitors of the DC filter (fig. from OC18 guidelines) equal to approx. 0.5 or 0.25 ohms at 1 MHz and 2 MHz respectively.
This seems to load the DDS output significantly
f (MHz), DDS att., V
1.0 5 distorted..
1.0 10 7.4 mV
1.0 15 4.4 mV
1.0 20 2.9 mV
2.0 5 distorted..
2.0 10 3.0
2.0 15 2.0 mV
2.0 20 1.5 mV
20 dB attenuator
f (MHz), DDS att., V
1.0 3 1.97 mV
2.0 3 ~500 uV (noisy)
Mu-Shields delivered. Inner and mid-shield unpacked - looks ok. Quite heavy duty material thickness!
Tomorrow: Check ASE-beam alignment (analog camera), RF trap drive OK?
15:03 no signal, dispenser off
Intensifier gain turned up, PCO exposure ca 100-200ms
14:51Z try to load with 2.0A. Now using image-intensifier and PCO camera.
Field of view now larger, both top and bottom almost in same view
NOTE: Image-intensifier input side is closer to the electrical wires. 3 wires: Orange (+5 to +15 V supply, 30 mA), White (Control voltage 0-5 V), Grey (Ground).
Use the old PCO-camera, to image the intensifier output plane
Install the (new) image-intensifier, this may help detect weak signals?
12:56 no signal, dispenser off
12:46 try load with 2.0A dispenser (2.3W initially)
check Rb-lines, they look ok
check 461nm with dispenser: 198.2 mA, 4.645 kOhm
12:32Z no signal, dispenser off
12:17Z try to load, 1.7A dispenser
remove PMT-splitter, to get more signal to camera. Use old imaging-objective. re-align objective to electrodes
(O-ring inside PMT-splitter-cube was loose?) blocking light thru lid is important
11:07Z no signal, dispenser off
10:53Z try to load, 1.7A dispenser
09:46 no signal, dispenser off.
09:32Z try to load, 1.7A dispenser
with old objective A-beam window reflection is quite strong, and exits the objective-tube towards B-beam post
new objective may have issues with beam window-reflections? Brass tubes used as spacers may need to be painted black?
test new imaging objective - but no huge improvement in image-quality of electrode image with flashlight illumination
realign camera to electrode image
08:52 no signal, dispenser OFF
08:37Z load with 1.7A dispenser
trap RF as before. monitor waveform seems jumpy!?
Optical power (slim sensor)
422nm A-beam 0.8uW, B 1.1 uW, C ~1uW
461nm A 200uW
405nm adjust to 3.7 mW
clearout 64 uW
repumper 10.6 mW
align A-beam with help of electrode reflections
remove inner shield (outer shield was removed yesterday).
win machine tilted? reboot.
13:28 no signal, dispenser OFF
adjust A-beam, based on output beam shape...(??)
13:15 try 1.7A dispenser, 1.7W
13:13 no signal, dispenser OFF
13:01Z try again with 1.6A Dispenser. 422nm Rb-lines checked, 405nm power checked. A-beam output doesn't look very clean (hits some aperture somewhere?)
12:50 no signal, dispenser OFF
12:47 no signal in 10min..
12:37:30Z dispenser on, 1.6A. 1.45W initially, rising slowly to 1.5 W
Try to load with 1.6A dispenser current
Trap RF from signal generator 10 Vpp, 14.424 MHz
monitor 64 mVpp
Preparing for trapping.
461 dispenser check, OK at I = 198.3 mA, T = 4.645 kOhm.
(New Thorlabs slim power sensor, model S130C)
422 power: A exit: 0.85 uW, B: 1.1 uW, C: 1.0 uW. Detuning at 185 MHz
461nm A-beam 195 uW
405nm A-beam adjust to 3 mW
repumper 13.5 mW (repeat 12mW) at ASE beam output
clearout 65 uW (seems low?)
(AW paper notebook clearout values: 75 uW on 2019-12-04, 77uW on 2019-11-25, 78uW on 2019-11-04)
New Kubuntu linux install
Installed new OS on new disk. Migrated all software.
Artiq version now: v5.7144.9ed8f663. Conda enviroment: artiq-ion-v5-6.
Ionclock ARTIQ now ident 5.7144.9ed8f663;mikes (autogenerated by M-Labs).
New drift-DDS ARTIQ now ident 5.7144.9ed8f663;mikes-drift (built manually).
Drift-DDS ARTIQ seems to work. Configured for external ref for both Kasli and Urukul.
(slight improvement with lid-adjustment and heatsink)
13:50Z add a heatsink to the alu end-plate
13:34Z improve slightly contact between antenna-lid and end-alumount. No visible reduction in monitor-voltage when loosening lid M3 screws (impedance matching still ok?)
With added clamping, resonator heating is reduced 140 -> 120 mK. RF-feedthru heating ~few mK lower.
(note the new year 2021 AD...)
Install 2pcs hose-clamps that push the Cu-resonator into contact with the Alu-mounts
12:13Z install clamps to breadboard on both sides of Alu helres-mounts
Heating of the RF-feedthrough flange (10Vpp from signal-gen, 6+ hours settling time):
|Old mount, no sink
|Old mount, Cu bars as heat-sink
|New mount, 2 mounts clamped
|New mount, mounts clamped, 2 hose-clamps around cu-helres
||66 - ~few mK (results 2021-01-14!)
Results with two alu-mounts clamped to breadboard, and no clamping-force between cu-resonator and alu-mounts.
Install new alu-mounts that imrpvoe heat-ocnduction from Cu-resonator to breadboard
11:26Z remove temporary copper heatsinks from helres
(TLi) New vented rf shield (0.1 mm copper) with 6-mm slots top and bottom:
ca 12Z move Pt100 ch. 6 (106) from rf shield to helical resonator cylinder, above adapter piece.
With old shield:
Signal generator (Vpp) Monitor (mVpp, average 32)
10 66.4 (without averaging ca 70)
New shield installed. RigExpert: min SWR 1.02 @ 14.4245 MHz, R = 52.1 Ohm, Q ~ 870 (SWR 2) ... 810 (SWR 3).
Signal generator (Vpp) Monitor (mVpp, average 32)
Both Q and monitor ratio as before within uncertianty.
ca 13Z ready
14:15Z RF OFF. will cool down by midnight, when computer turns ON.
RF siggen to 10Vpp, turn ON for testing
lab lights (partially)
ca 09Z Turn on stuff after x-mas break
For 2020 results see index_2020
For 2019 results see index_2019