TOC/References - Notes - Comb - Ion - Cavity - DAQ

News and notable results

2022-08-12

2022-08-08

Measured power seems to agree with model, using optimal RF-power P0 = 1.3*Pmax_used
single-pass model is I/I0 = sin**2 [ (pi/2) * sqrt(P/P0) ]

small-angle approximation sin(x) ~ x for small x.
-> I/I0 ~ P single-pass, and I/I0 ~ P**2 double-pass

When this scaling holds, we expect 10 dB of reduction in optical power (OD1-filter) for each 5 dB of reduced RF power.

With RCDAT inserted after PA, 0dB setting, now ARTIQ attenuation ca 15 dB seems OK.

RCDAT  P674
0      3.8 uW
3      1.78
6      605 uW
9      177 nW
10     112
11     71.8
12     49
13     31
14     19.8 nW
15     12.9
16     9.1
17     6.0
18     4.0
19     2.6
20     1.9
21     1.3
22     1.0
23     0.8
24     0.6
30     0.4
40     0.4
50     0.4
off    0.4  (artiq DDS off)

Test 674nm power vs. AOM RF drive power, old configuration (no adjustable attenuator)
674nm power-servo set-point to 2.0 V, lab lights dark, detector-area covered with holy-blanket
Thorlabs slim detector after 461-cube, before B-fiber

Detector dark: 0.2 nW
18 dB DDS att   4.03 uW
19  3.45 uW
20  2.75
21  2.15
22  1.58
23  1.13
24  0.77
25  0.53
26  0.36
27  0.24
28  0.16
29 105 nW
30 67 nW
DDS off 0.5 nW
18 4.00 uW
17 4.35
16 4.42
15 4.24
14 4.08

AA Optoelectronics whitepapre on diffraction efficiency:
I1/I0 = sin**2 [ (pi/2) * sqrt(P/P0) ]
this formula for single-pass, we use double pass.
Note RF PA may go into saturation at high power-levels!

2022-08-03

2022-08-02

Summer break 2022

2022-07-01

09:37 ion still stored
uMotion check: 1.4%, 1.0%, 0.3%

Optical disturbance from Comb-computer screen at 60Hz is significantly less when brightness set to 100%
Some 50 Hz optical disturbance still from first room emergency-light and normal lab-lights

Drive fiber-noise AOM with fixed 178.5 MHz requency from R&S generator
this allows turning off LDS12B PSU that was powering fiber-noise detector
(but what could be sensitive to AC magnetic field in the cavity or PDH-lock?)

Check fiber-coupling of 422nm laser to ion breadboard, only ca 2-3 uW in B-beam before B-beam fiber, with slider pos1 (no filter)

2022-06-30

ion dark
stop clock-run, all beams on, clearout on
ion recovers

uMotion: 1.7% 2.8% 0.4%

Measure AC-magnetic field with Magcheck-95e probe
Sensitivity 1 mV AC = 1 mG = 0.001 * 0.1 mT = 0.1 uT 
(1 G = 1e-4 T = 0.1 mT )
Sensor vertically on top of outer shield, above ion
Horizontal orientations give significantly smaller measurements, so most of AC B-field vertical?
Measure with Rigol RF-monitor scope, DC-coupling, 1 MOhm

7 mVpp with Thorlabs LDS1212 on (this caused severe sidebands previoulsy)
3.2 mVpp with LDS1212 off
no visible change with PMT off/on
123 mVpp when sensor placed at back of BOA laser-driver (Thorlabs ITC510)
3.8 mVpp with sensor on top of outer shield, helres end
7.8 mVpp top of outer shield, ion-pump end
1.4 mVpp with sensor on trap-breadboard, next to helres mount
1.98 mVpp measured with black Keysight scope (sensor on top shield above ion)
1.96 mVpp with Rigol scope off
0.56 mVpp main optical table, next to helres mount
0.11 mVpp lab floor
1.9 mVpp back to top of outer shield, above ion
disconnecting 11mA I2 current has no effect
disconnecting brick PSU for 461nm doubler temperature-controller -> no effect
5.7 mVpp with LDS1212 on

mis-aligned B-beam while playing with magcheck sensor??
14:46 after some searching, found B-beam alignment again.

17:20 check uMotion: 0.97%, 2.1%, 1.9%
Fluorescence-level seems low, but this is because 422nm power is low. ca 2 uW in A-beam befre fiber (usually 10% of this in B-beam after objective, towards ion)

2022-06-29

2022-06-28

09:25 ion still stored. fluorescence quite weak, B-beam counts 29.4 / 0.7 in 10ms (slider pos3?)
30kphoton uMotion A 0.9%, B 5.6%, C 12.6%
(uMotion program hangs when creating figure?)

Block extra light from reaching PDH-detector
- Green LED on EOM (indicating temperature stability) blocked with Cu-tape
- Lights on cavity ion-pump controller blocked with black cardboard flaps

Try slide pos6 for more fluorescence!?

ID23698 Try running 20 iterations of u-motion minimizer, 40 kphotons/pt
Set old bias-voltages V12cm , V12diff, V34cm, V34diff = [ -6.47, 0.26, 23.43, 59.5]
(out-of-repo works?)
optimized voltages V = [-6.4700 0.2371 23.3268 60.4094 ]

verify after optimization: 0.8%, 1.4%, 1.8%

2022-06-27

With comb rep-rate at 250 MHz we get beat-notes:
 fb1 109.71 MHz
 fb2 140.19 MHz
These could both be mixed down to <30 MHz for SDR with e.g. LO = 120 MHz
giving
 fb1_mix = -10.29 MHz
 fb2_mix = +20.19 MHz

Usual fb1 = -15.5 MHz, ncomb = 889558, f0 = -35 MHz, frep = 249999896 Hz
 f_ir = f0 + ncomb*frep + fb1 = SRS/2 - 165 MHz

With 250 MHz frep and fb1=-109.71 MHz we get: SRS/2 - 166.7 MHz (two cavity modes off from correct mode?)
(check with rep-rate dds at 19 999 584 Hz -> beat-note at 17.4 MHz)
 - higher piezo voltage, next mode 16.8 MHz
 - next mode 16.1 MHz
 - next 15.5 MHz - this is the correct one!
back to 250 MHz rep-rate: beat note at 108.0 MHz (this gives same SRS-165 MHz result for the IR frequency)

Check 50Hz and 100Hz background light with Thorlabs amplified detector (AC coupled to scope)
- sine-shaped disturbance from emergency-exit sign? (block this, or block window between lab and first room?)
- square shaped disturbance from comb computer screen!!?? (must close door between lab and first room!?)

2022-06-24

2022-06-23

09:45 ion dark
 - all beams, clearout on
 - 405nm on
 - slider pos1
 - (some time later) ion has recovered!?
 - back to B-beam, slider pos2
 - went dark again?? slider unlocks Rb-lock??
 - relock to Rb-line
 - after some minutes ion re-appears..
 - PMT counts low even with slider pos1 -> low 422nm power?
 - was locked to wrong Rb-line, after another re-lock fluroescence is much brighter again

B1 estimate =  4.821564486979048
(with same coil currents we now get significantly lower B-fields?)
2022-06-20: 4.8302 uT
2022-05-17: 4.8404 uT

2022-06-22

2022-06-21

Changes made: 
- ECDL, BOA, doubler now on main optical table (cable and fiber-lengths very similar to old setup)
- EOM drive PA now new 1 W mini-circuits
- more filters in PDH-loop to suppress 2*25 MHz from PDH-detector and 25 MHz through FALC servo
- new PDH detector based on OPA818 with (much) better noise floor - seems shot-noise limited at 25 MHz

2022-06-20

+C1 FWHM 1955 Hz AOM, height 34
-C1 FWHM 1990 Hz AOM, height 57.1
B1 estimate =  4.837593013831374
+C2 FWHM 2110 Hz AOM, height 45.4
-C2 FWHM 2042 Hz AOM, height 20.89 ??
B2 estimate =  4.840632485343382
+C4 FWHM 2365 Hz AOM, height 30.4
-C4 FWHM 2103 Hz AOM, height 10.7
B4 estimate =  4.835183060655167

+C1 FWHM 2004 Hz, height 31.4
-C1 FWHM 2128 Hz, height 40.5
B1 estimate =  4.830021041684657
+C2 FWHM 1914, height 50.7
-C2 FWHM 1998, height 36.7
B2 estimate =  4.825156783993923
+C4 FWHM 2022, height 44.7
-C4 FWHM 2127, height 36.1
B4 estimate =  4.830219685373228

2022-06-18 kiky Saturday

2022-06-17

2022-06-16

2022-06-15

25 MHz peak in PDH-signal:
low-pass filter on FALC input?
There is a clear 25 MHz peak in the downmixed PDH errorsignal also, BLP-15 reduces this peak

no-filter  -12 dBm
BLP-15     -13 dBm on PDH-detector (ca 30 dB insertion loss at 25 MHz)
NOTE: with BLP-15 filter need to change LO-angle by almost 180 degrees! now 96.4 deg

With AA 34 dB PA, -6.2 dB EOM drive-level seems optimal?
transmitted photodiode 
Carrier 1.8 V
lower sideband 1.15V
cant find the other sideband: this may be the problem causing 25MHz on PDH-detector: + and - sidebands not equally strong?

Try mini-circ PA instead?
Signals improve significantly with lower EOM-drive level! Previously high drive-level caused high-order sidebands!?
Up to 3.9V on cavity-transmission detector

Now -13.2 dBm (Toptica source), +34 dB (AA 2W PA), BLP-30 = +20.8 dBm
674nm power:
ca 31 uW at corner, before EOM
ca 21 uW towards cavity, after final mirror
ca 17 uW at PDH-detector

PDH detector
1.55 VDC when laser unlocked
1.1 VDC when laser locked
3.4 VDC on cavity-transmission detector
-14.2 dBm from Toptica source might give slightly more cavity-transmission
PDH-mixer input level at +10 dBm
LO-angle at 135 degrees

Final optimized settings from PDH-tuning today:
EOM-drive -14.2 dBm from Toptica, with AA 34dB PA and BLP-30 filter before EOM resonance-circuit
+10 dBm input level on Toptica PDH-mixer
135 degree LO-angle
BLP-15 low-pass filter on FALC input
20dB attenuator on FALC output
FALC SLI: pos 6 
FALC FLD: pos 6
FALC FLI: pos 7

2022-06-14

PDH-spectrum via 10dB coupler on PDH-detector
unlocked:
* 50MHz -55.5 dBm (ca +20 dB above noise-floor)
* 25 MHz ca -60 dBm (ca 10 dB above noise-floor)
locked:
* 50MHz ca -45 dBm (up +10 dB from unlocked)
* 25MHz ca -14 dBm 

Increase drift-comp AOM drive-level, ARTIQ-attenuation now 18 dB (script: drift_comp_v4.py)
Cavity-transmission photodiode now up to 1.1-1.2 V

2022-06-13

Continue with clock-laser
PDH-mixer now external ZAD-6 mixer with LPF-30 filters on both LO and RF(PDH-detector)

RF-drive -15.2 dBm (seems optimal?) from Toptica to 2W AA-amplifier
Nominal gain 34 dB -> -15.2+34 = +18.8 dBm to EOM/resonance-circuit
LO-angle 270 deg

PDH-detector ca 550-560 mVDC when locked - same voltage when unlcoked? (very little coupled into cavity?)
cavity transmission detector ca 350 mV (300mV with lab lights off)

Cavity temperature control was not working for about 4 days. Now should work again?
Inner shield temperature ca 32.56 C, higher than normal

ca 14:30 local cavity-transmission up to 0.45 V
PDH detector, locked 530 mVDC, unlocked 540 mVDC
674nm power
- at corner before EOM ca 13 uW
- towards cavity after last mirror ca 8.2 uW
- at PDH-detector ca 6 uW

FAIL: reason for problems was FALC main-output connected to laser-head AC-mod, correct input is DC-mod!!
with correct cabling laser locks similar to earlier.
large 25 MHz spike in PDH-detector signal (RAM, or RF-pickup from EOM-drive?)

2022-06-10

Continue with clock-laser
comb rep-rate at 20 MHz DDS -> 250 MHz rep-rate

laser locks to a mode at 109.1 MHz beat-note, with LO-angle around 0 degrees
mode around 116.6 MHz with LO-angle 212deg
 
PDH-signal spectrum ugly with spikes at +/-780 kHz?

2022-06-09

674nm power measurements. ECDL at usual 170 mA setting, BOA at 500 mA.
(comparison measurements e.g. 2022-01-31 and 2022-02-03)

to cavity-system (fiber output, before isolator): 1 mW
to ion (fiber output, before fibernoise retroreflector): 107 uW

Cavity input-end corner (before EOM): 14 uW
PDH-detector: 7 uW

674nm doubler temperature display: 48.7 C

Got laser locked to cavity, but with large servo-oscillation peaks?
Seems to work only in narrow range of main-gain trimpot

2022-06-08

Check EOM drive-level at end of long Aircell SMA-cable, close to cavity-box

Toptica dBm    SA dBm
-12.2          -12.2   seems OK
(see notes from 2022-02-11 where Toptica source -> PA -> dummyload was verified)

Toptica (-12.2dBm) -> (10dB att) -> PA -> dummyload -50dB port measures -25.6 dBm - seems OK
(compare to -17 dBm dummyload(-50 dB) port measured without 10 dB attenuator)

With 10 dB attenuator Toptica setting for drive-level probably -15...0 dBm OK?

Overall PDH-lock gain seems weak compared to previous configuration.
With 20dB attenuator removed from FALC-output (to ECDL current-mod in) get a weak fluctuating lock.
EOM-drive from Toptica ca -6...+0 dBm, LO-phase maybe 60 deg.

2022-06-03

After yesterdays power-cut:
- comb f0 lock unlocked, servo at limit?
- comb frep unlocked, servo at limit
-- comb auto-control has servoed comb-temperature down to 21.5C from usual 25.5C setting
-- manually set usual setting 25.5 C
-- adjust stepper-motor to get frep within locking-range
-- temperature seems to settle slowly - need to wait 1h or more?

- clock-laser seems still locked
-- 15.5 MHz beat note had jumped one cavity-mode lower, ca 14.8 MHz now
- coolinglaser seems locked to Rb-line
- ion dark or lost?
- bias-voltage and coil-current drivers seem to have rebooted!?? all values zero?
- Siglent PSU above trap-setup has rebooted and outputs are off
- Siglent at back of rack (Zeeman AOM PA supply etc) seems on - not rebooted
- 

set usual bias voltages and coil currents:
V12cm , V12diff, V34cm, V34diff = [ -6.47, 0.2053, 23.3835, 59.4433]
- coil currents fail, no connection to driver at 192.168.10.7 ?
- rebooting coil-driver fixes problem with Ethernet connection
I1 = -0.0408, I2 = -11.4939, I3 = -0.7741

To get beat-note measurement ch2 to work, need to set ARTIQ DDS ch2 again to 215 MHz
This means ARTIQ-box has also rebooted to some extent during power-cut??

2022-06-02

connection to artiq-box lost at power-cut?

computer did not reboot:
$ uptime
 19:05:53 up 176 days,  1:46, 26 users,  load average: 2,53, 2,12, 2,07

ca 19 ion dark.

2022-06-01

2022-05-31

2022-05-30

15:42 load with 1.75A
12:58 ion! 

check initial uMotion RIDs 23472,3,4
3.1%, 1.9%, 3.5% - OK

voltages are low-EQS setting from last run: [ -6.47, 0.2053, 23.3835, 59.4433]

16:09 try to start 100ms/OD4/28dB clock-run, to see laser-drift and abs(B) for today
16:39 set slider pos3, OD0.8? to get more fluorescence, with pos2=OD1 got ca 30 counts/10ms - leads to false-dark events with threshold=10?
17:00 ion went dark - recover manually with slider pos1, 405nm, all beams

2022-05-27

06 ion dark, stop clockrun, recover?
 ion lost?

14 local turn off lasers, comb

2022-05-26

ca 21:20 continue with interleaved lo-hi EQS clockrun
 OD4/28dB/100ms, g1=1.0, g2=0.01, n_shots=30
 cycle time 104.9s (12 servos)
 lo-eqs servos seem locked, ccounts ok
 hi-eqs C4+ counts low or zero?

21:41 restart clockrun

Automated tickler runs for changing V12cm
V12cm  X         Y        Z          RIDs
-6.5   907711.6  955162.2 1950047.8  23297,8,9
-7.5   875848.8  924916.1 1980681.1  23301,2,3

new schedule with wider scans to find resonance
       X         Y         Z 
-6.5   907683.4  955142.6  1950014.4  23342,3,4
-7.5   875850.4  924967.1  1980706.3  46,7,8
-8.5   842822.7  893740.8  2010837.4  50,1,2
-5.5   938505.4  984338.2  1918779.9  54,5,6
-4.5   968255.2  1012785.5 1887121.2  58,59,60
-3.5   997088.9  1040426.2 1854927.9  62,3,4
-2.5   out-of-range        1822235.2  66,7,8
-1.5   out-of-range        1788866.0  70,1,2
-0.5   out-of-range        1755077.9  23376
+1.5   not run
-6.5   not run

Fit 2nd-degree polynomial to above results, and center scan around this?
once more:
V12cm X         Y        Z          RIDs
-6.5  907646.8  955065.3 1949894.6  23387,8,9
-7.5  875804.7  924939.1 1980592.4  91,2,3
-8.5  842777.9  893697.1 2010644.3  95,6,7
-5.5  938396.6  984326.8 1918689.0  99,23400,23401
-4.5  968178.6 1012741.3 1887046.6  403,4,5
-3.5  997103.2 1040381.1 1854858.1  407,8,9
-2.5 1025147.1 1067295.0 1822143.2  411,2,3
-1.5 1052521.0 1093522.4 1788870.8  415,6,7
-0.5 1079167.4 1119204.7 1754848.3  419,20,21
+0.5 --------- 1144265.2 1720316.1  423,4,5
-6.5  907639.9  955042.5 1949814.7  427,8,9

2022-05-25

15:09 load with 1.75A
15:21 ion, soon after tuning 422nm to 185 MHz detuning, so maybe this improves loading (although loading works at 208 MHz detuning also)
ID23241 pmt-counts during loading

uMotion 2.5%, 6.3%, 4.2%

bias voltages at [ -6.5, 0.2053, 23.3445, 59.4433] 
last secular freqs are 2022-04-05: 912.6, 959.7, 1957 kHz x,y,z
(Z**2)/(X**2+Y**2) = 2.18369

X-search: 909-916 kHz, 15 dB att (20 dB fixed attenuator on DDS), 5 kphotons/pt
Y also with 15 dB
Z with 24 dB


V12cm V34cm    X        Y        Z          R=Z**2/(X**2+Y**2)
-6.0  23.9945  923570.1 970254.5 1935144.2  2.0870 (+15.6, +14.9, -15.3 kHz)
-6.5  23.3445  908011.5 955401.8 1950461.1  2.1898
-7.0  22.6945  892321.0 940501.8 1965930.8  2.2994  (change from -6.5V delta X,Y,Z: -15.7, -14.9, +15.5 kHz)

rough model for seculars (from single-voltage secular scan experiment)
(coefficients for V34cm are 50-fold smaller, not relevant for finding resonance here)
X + 30 kHz*V12cm
Y + 28 kHz*V12cm
Z - 30 kHz*V12cm 

2022-05-24

2022-05-23

For fun, try a clock-run with lower g1? Our clock-laser is better than QPN at 1 servo-cycle in any case?
100ms clock-run with g1=0.2, g2=0.01, n_shots = 30

C = -0.0159 0.0435 0.0189 RMS = 0.0500
V = [-6.5000 0.2053 23.3445 59.4433 ]
dV = 0.0207  -0.1350  0.3892

2022-05-21 evening session

20ms peak-search
C1+ Center =  75.83798798965832, FWHM 95 Hz AOM
C1- Center =  75.81066871743741, 103 Hz
B1 estimate =  4.8679716376506414

C2+ Center =  75.85155768902926 (FWHM 104 Hz AOM)
C2- Center =  75.79709159130498 (109 Hz)
C2 Linecenter =  75.82432464016712
B2 estimate =  4.868021776190824

18:57 start 90ms clock-run
now at last uMotion-optimizer voltages of V12cm , V12diff, V34cm, V34diff = [ -6.5, 0.1846, 23.4795, 59.0541]
19:03 restart with better line-center
19:18 restart with B 4.86816 uT, probe to 100ms (better p_exc?)
-- cycle time 52.24 s, dead-time 45.1 ms as usual
-- abs(B) seems to settle around 4.86813 uT

EQS-schedule
22:00 to -8.5 V ( 2V steps, 4h data per step )
02:00 to -6.5 V
06:00 to -4.5 V
10:00 to -2.5 V
14:00 to -0.5 V
18:00 to +1.5 V
22:00 to +0.5 V (back to -6.5V in 1V/1h steps)
23:00 to -0.5 V
00:00 to -1.5 V
01:00 to -2.5 V
02:00 to -3.5 V
03:00 to -4.5 V
04:00 to -5.5 V
05:00 to -6.5 V

2022-05-21

Summary of AT-search:
- no clear AT-split seen
- I2 current stepped in 0.1 mA steps from 1.24495 A to 1.24615 A 
- A2 coil sensitivity estimated at ca 0.41307 uT/mA, in agreement with previous results
- Clock laser stable during run, line-center ca 75.824326(2) MHz AOM
- C2- component measured, because it was strongest
-- smallest shift C2- at  72.9469 MHz -> 514.35 uT
-- largest  shift C2- at 72.9441 MHz -> 514.85 uT

AT-split expected when ground-state split equals RF frequency
omega_S = g_S mu_B B0 / hbar
-> B0 = omega_RF hbar / (g_S mu_B) = 514.6398 uT with electron g_S 2.002319

OD4/18dB/20ms spectra, 6Hz step 600 Hz span
C1+ Center =  77.26829496893637 -> B = 514.5967 uT, FWHM 98 Hz AOM (Fourier limit 20 Hz AOM)
C1 Linecenter =  75.8243250019277
B1 estimate =  514.5967863403096

C2+ Center =  78.70314602662296
B2 estimate =  514.6005831797813

A = 514.5 uT/ 1245.55 mA = 0.41307 uT/mA
Z2 = 11.1885 kHz/uT, peak moves out of 10 kHz AOM span at deltaB = 10 kHz/11.1885 kHz/uT = 0.9 uT
0.1 uT step corresponds to deltaI = 0.1 uT / A = 0.242 mA

deltaI 0.2mA should move C2 peak 0.924 kHz optical
we measure C2- so smaller current (smaller B) moves peak up in frequency

I2 (mA)   C2-
1245.55   72.9455
1245.35   72.946

2022-05-20

Final contrasts C = -0.0036 -0.0323 0.0365 RMS = 0.0488
V = [-6.5000 0.1846 23.4795 59.0541 ]
dV = -0.0404  -0.1082  -0.9492

OD0/18dB/200us (yesterday maybe used 400us probe with OD0/18dB and only I2 current?)
C1+ Center =  76.3462834288485
C1- Center =  75.3025162529413
C1 Linecenter =  75.8243998408949
B1 estimate =  185.9869826524296

C2+ Center =  76.86428069815916
C2- Center =  74.7845072404588
C2 Linecenter =  75.82439396930897
B2 estimate =  185.88411699475427

Double to -900 mA, estimate is 371.76823398950853
voltage over coil 468 mV giving 0.9*0.468 W = 421 mW dissipiation
+C1 Center =  76.86781562179468 (not so great fit)
-C1 Center =  74.78168881233164 (not good fit)
C1 Linecenter =  75.82475221706315
B1 estimate =  371.7231578825482

+C2 Center =  77.90455998261733, FWHM 2178 Hz AOM (Fourier limit 2 kHz AOM)
-C2 Center =  73.74426133849755, FWHM 1955 Hz
C2 Linecenter =  75.82441066055745
B2 estimate =  371.8354213212059

For 514.6 uT, current estimate based on last measurement 1245.5510 mA
set I2 = -1245.55 mA. Dissipation 1.24555*0.649 W = 808 mW
+C1 Center =  77.26860020582984 
-C1 Center =  74.38059887069626
C1 Linecenter =  75.82459953826304
B1 estimate =  514.6077272940057

+C2 Center =  78.7030822575593, FWHM 1889 Hz
-C2 Center =  72.94554541626057, FWHM 1941 Hz
C2 Linecenter =  75.82431383690994
B2 estimate =  514.5919368511186

Keep same current setting, switch to OD2 and 10-fold resolution
OD2/18dB/2ms spectra
+C1 Center =  77.26828296565073, FWHM 201 Hz
-C1 Center =  74.38036757719466
C1 Linecenter =  75.8243252714227
B1 estimate =  514.5924126112019

+C2 Center =  78.70311178598891, FWHM 213 Hz
-C2 Center =  72.94554256322625. FWHM 224 Hz
C2 Linecenter =  75.82432717460759
B2 estimate =  514.5948310124063

Switch to OD4 for 10-fold resolution
OD4/18dB/20ms spectra. 400 Hz span, 4 Hz step, 101 pts/peak
B2 estimate =  514.5976829710373

2022-05-19

Back to usual coil currents I1 = -0.0408, I2 = -11.4939, I3 = -0.7741

test clock-run with 4ms/OD2/18dB as sanity-check, C1 linecenter ca 75.82426

17:07 start 80ms/OD4/28dB clock-run?

18:30 start 80ms clock-run with initial B from 20ms spectra
19:00 restart
19:20 restart again (C1, C2 B-estimates ok)
19:40 seems locked and OK

schedule for voltages
19:40 - 22:45  -6.5 V
22:45 - 01:45  -8.5 V (V34cm 20.9877)
01:45 - 04:45  -4.5 V (26.1877)
04:45 - 07:45  -2.5 V (28.7877)
07:45 - 10:45  -0.5 V (31.3877)

2022-05-18

coil-currents nominal setting is I1 = -0.0408, I2 = -11.4939, I3 = -0.7741
set I1=0, I3=0, I2=+11 mA

200us spectra:
C1+ at ca 75.8385, height only 10/100 with 200us, Center =  75.83849932779522
C1- at ca 75.8105, even lower height due to S-balance, Center =  75.81046256356215
B1 estimate =  4.995820239808815

Switch to Siglent power-supply for I2 = 11 mA, try spectra with 400us
C1+ ca 75.840
C1- ca 75.808
B guess ca 5.7 uT

double current to 22 mA, guess is 11.4 uT. PSU reads 22 mA and 13 mV
peak-search with 800us probe
C1+ ca 75.8585, corresponds to ca 12.2 uT ? only 4/100 counts with 1000us probe
try rabiflop to find good probe length? 

back to Tomberg current driver, I2 = -11.4939, other currents 0
200us gives good counts 38/100
Center =  75.837844309115 -> ca B 4.82687 uT

double to -23mA, guess is 9.6 uT
200us C1+ gives lower counts 20/100
Center =  75.85089231997432 -> ca 9.4768 uT
rabiflop gives longer tau_pi ca 400 us

double to -46 mA, guess is 18.9536 uT
400us spectrum, 35/100 counts
Center =  75.87744390626217 -> ca 18.93923 uT

double to -92 mA, guess is 37.87846 uT
400us spectrum 22/100 counts
Center =  75.93069195621851 -> 37.9259 uT

double to -184 mA, guess is 75.85182976 uT
400us spectrum 24/100 counts
Center =  76.03731458101723 -> 75.923699693 uT

double to -368 mA, guess 151.8473993874 uT
400us spectrum 23/100 counts
Center =  76.25073779014917 -> 151.98268987980717 uT

Switch to Siglent PSU and set same current -368 mA. Siglent shows power 72 mW
400us spectrum
ion went dark :(
ID22805 try again, C1+ peak at Center =  76.25044713947645 -> 151.8791088458876 uT
C1- at Center =  75.39736589491767
peak-separation gives 152.0090019 uT

Double to -736 mA, guess is 304 uT. Siglent shows dissipation 289 mW
24/100 counts, C1+ at Center =  76.68031272359639 -> 305.0741177 uT
C1- at Center =  74.97154384933688
peak-separation gives B1 estimate =  304.48243086173903 uT

target is 514.6 uT, for this we want ca 1241.487 mA
set 1241 mA, Siglent shows dissipation 825 mW initially, dropping to 804 mW in 1-2 min
400us spectrum, counts 30/100
C1+ at Center =  77.26628267443004 -> 513.899966 uT
C1- at Center =  74.38209094926103
B1 estimate =  513.9288997942084 uT
current for 514.6 uT would be 1242.620 mA

set 1243 mA, dissipation 808 mW
C1+ at Center =  77.26889938168418 -> 514.8324989065194 uT
C1- at Center =  74.38197661585203 (seems wrong? gives line-center with large offset to comb prediction?)
B1 estimate =  514.415538983639

siglent IP for remote control 192.168.10.58

C1+ Center =  77.26880417156454
C1- visually ca 74.3796 (this gives line-center within 70 Hz AOM of comb-prediction - ok)
C1- Center =  74.37959783673728
B1 estimate =  514.822444006984
C1 Linecenter =  75.82420100415091
comb pred.    =  75.824270

C2+ Center =  78.70431166691162 giving estimate B2+ 514.8198924 uT
C2- print:Center =  72.94418412527843
C2 Linecenter =  75.82424789609502
B2 estimate =  514.8234861298571

Ingoring B0, this gives A(2) = 0.414178 uT/mA roughly in agreement with previous measurements

next try a lower current, possibly non-resonant?
I2=-1240 mA with prediction 513.580951569608 uT
B1 estimate =  513.590341541764
B2 estimate =  513.5569082755302

I2=-1230 mA, prediction 509.43917 uT
C1+ Center =  77.25365320214294
B2 estimate =  509.3861133798284

I2=-1200 mA, prediction 497.01382409962065 uT
C1+ Center =  77.21869030452979
B1 estimate =  496.9322033358911
B2 estimate =  496.9305133715476

I2=-1100 mA, pred. 455.5960054246523 uT
C1+ Center =  77.10261091315833 -> 455.5705 uT
B1 estimate =  455.61677559155976
B2 estimate =  455.63955267289623

2022-05-17

11:17 load with 1.75A
11:26 ion! ID22653 is pmt-counts during loading
slider to position 2, OD1 filter for 422nm (rb-lock stays locked)
uMotion 100kphotons: A 9.7%, B 21 % (!), C 19%

V = [-6.5000 0.2250 23.5877 59.0033 ]
final contrasts C = 0.0070 -0.0077 0.0152 RMS = 0.0185

Check validity of EMM-preserving voltage vector [1, 0, 1.3, 0] V
V12cm  V34cm     uMotion
-6.5   23.5877   [1.3, 1.7, 1.6] % (initial point after optimization, see above)
-4.5   26.1877   [2.4, 2.1, 2.1] %
-2.5   28.7877   [1.4, 0.7, 2.4] %
-0.5   31.3877   [2.8, 2.7, 3.2] %
+1.5   33.9877   [2.9, 1.6, 1.7] %
+3.5   36.5877   [0.9, 1.7, 3.0] %
+5.5   39.1877   [2.1, 1.9, 4.7] %
+6.5   40.4877   [2.1, 1.8, 3.3] %
-6.5   23.5877   [0.7, 2.0, 2.0] % (IDs 22707,8,9) (back to initial point in 3 steps)
-7.5   22.2877   [1.0, 0.9, 1.4] % (ID 22711,2,3) (this point has EQS with opposite sign to others?)

From last clock run initial estimate was B= 4.843 uT
B1 estimate =  4.816310740308461
C1 Linecenter =  75.8236721290117
B2 estimate =  4.838068367818707
C2 Linecenter =  75.8236972583399
B4 estimate =  4.840377332692647
C4 Linecenter =  75.82369446017181

C1+ peak at 75.8373146
C1- peak at 75.8101594
this gives B1 estimate 4.838735

try clock-run with 80ms probe. now at -7.5 V12cm
  initially Dsum did not converge, was stuck at -50 Hz
16:36 restart with B-estimate from C1 and C2 pairs 4.8399 uT
17:40 one hour of OK clock-run, Dsum OK, EQS-slope as expected slightly negative
  clock-laser shows periodic oscillations with period ca 60/5 = 12 min? amplitude ca 5 Hz at 674 nm

16:45-19:45 at V12cm -7.5 V
19:45 to V12cm -6.5 V 
22:45 to V12cm -5.5 V
01:45 to V12cm -3.5 V
04:45 to V12cm -1.5 V
07:45 to V12cm +0.5 V

2022-05-16

2022-05-10

2022-05-03

Pinkert2015 thermal expansion and refractive index temperature coefficients
alpha_L = 5.6e-7 /C
alpha_n = 1.06e-5 /C

d(fi) / dT = (omega0/c) [ L*alpha_n + L*n*alpha_L]
n(1550nm) = 1.4682 for telecom-wavelength

For 674nm this gives prediction of 106 rad / degC phase change per 1m of fiber (?)
For 1348nm prediction is 53 rad / degC per m of fiber.

Fiber from ECDL to comb is P3-1310PM-FC-10
from 674nm doubler to cavity P3-630PM-FC-5
from cavity to ion-breadboard also P3-630PM-FC-5, length is 5m (+short fiber from breadboard-corner to 674nm launch below helres)

measured phase/temperature correlation ca 500 rad/C, corresponding to 50% of cavity->ion 5m fiber reacting to ambient lab temperature - plausible result.
single-pass frequency shift: 0.5*500 rad/C / (2*pi 1/s) = 40 Hz / (C/s)

For the ECDL->comb fiber 10m * 53 rad/degC/m = 530 rad/degC = 530/(2pi) Hz / (C/s) = 84 Hz / (C/s)

If a clock-run starts at T0, duration is 24h, and ends at T0 + 1 degC we get:
f_shift = [84 Hz / (C/s) ] * (1/(24*3600)) = 1 mHz IR = 2 mHz 674nm = 4.4e-18  shift / (deltaT/day)

2022-05-02

AOM signal from R&S generator, set to 178.501 MHz gives 2 kHz beat-note

See [Kazda2015] and [Tyumenev2016] for similar plots
Kazda ca -12 mHz shift (0.2 degrees in 125 ms) with 1 W RF power (short off-time!)
Tyumenev  -45 mHz, -20 mHz, -5 mHz using 1.7 W, 0.537 W, and 0.17 W RF power

Shift scales linearly with RF power, as expected
Campaign setting of 28 dB attenuation corresponds to +17.9 dBm RF power (62 mW) at AOM
our 'max' setting is +10 dB from this, +27.9 dBm = 617 mW

With 30 min on-time, residual slope at end of run is <1 mHz, so we are confident that the mixing-frequency is correct.

With Tp=80ms, Td=45ms, we expect duty-cycle scaling (1-Tp/(Td+Tp)) = 0.36

2022-04-29

17:20 start 60 hour AOM-chirp measurement
1800s on, 1800s off. 10 repeats, so 10 hours per attenuation
6 different attenuations from 18 to 28 dB: [18., 20., 22., 24., 26., 28.]

60 hour run should finish by 5 am local on Monday morning

2022-04-28

Leave AOM-chirp run over night
1800s ON, 1800s OFF. initially 18 dB AOM attenuation, 10 repeats
SDR HW tune  151664009.99845859408378601074, SW tune +1 kHz
expect -178 uHz correction needed (see below)

Test SDR frequency measurement accuracy against ARTIQ DDS
ARTIQ settings Frequency in MU:  21344951171411
Actual frequency in Hz: 75832500.000000626
deviation from programmed frequency:  +6.258487701416016e-07 Hz
   2*fAOM = 151665000.00000125
SDR RX tune 151664004.99910995364189147949
SDR f-translation in software +1 kHz

expected measured frequency: 4.999108701944 Hz

when unwrapping phase with this frequency, get a positive residual of:
0.001348 rad/s = 0.000215 Hz  (dataset length ca 100s)
if we subtract this from the expected measured frequency
and unwrap with: 4.998893701944351 Hz we get essentially a zero-slope residual

repeat with SDR frequency tuned to be ca -10 Hz
SDR HW Rx 151664009.99845859408378601074
f-translation +1 kHz

expected frequency: 9.998457342386 Hz
phase-residual 0.001121 rad/s = 0.000178 Hz
corrected frequency 9.998279342386246 Hz -> phase residual below 1 uHz

With knowledge of this correction, try to measure equilibrium beat-note again..

2022-04-27

Second AOM-chirp run over night
Attenuations:  [18. 21. 24. 27. 30.] dB
ON for 300s, OFF for 600s
10 repetitions for each attenuation

2022-04-26

Attempt to measure AOM chirp.
Reference beam before Zeeman-AOM, shifted beam is B-beam after cube/B-shutter
60MHz one-inch-photodetector + Mini-Circ ZFL amp give ca -55 dBm signal (AOM at 75.8325 MHz, so beat-note at 151.665 MHz)
Measure with B210 SDR, downconverted signal stored at 200 S/s.

artiq programmed measurement sequence:
AOM on for 120s 
AOM off for 600s
repeat 10 times.

These 10pcs on/off cycles are repeated at different attenuations:
18 dB down to 28 dB in 5 steps
as attenuation is increased, we will loose SNR for the beat-note. 28 dB attenuation gives <5% of power at 18 dB

From ARTIQ AD9912 DDS, frequency setting is:
Frequency in MU:  21344951171411
Actual frequency in Hz: 75832500.000000626
deviation from programmed frequency:  +6.258487701416016e-07 Hz

2022-04-25

2022-04-22

2022-04-21

2022-04-20

2022-04-19

06:11local change aux-servos to measure carrier max peak height (slave-servo FWHM=0, both R and B measure carrier peak)

11:32local stop clock-run

Zeeman
AOM att   tau_pi approx    spectrum step Hz AOM
28        70-80 ms         1 Hz
23        40 ms            2 Hz
18        20 ms            4 Hz


2022-01-09 coil-characterization B0 = [1.222, 0.1271, -0.2233]
abs(B0) = 1.249 uT

B2 estimate =  1.2424556640503752
B4 estimate =  1.2424622174806619

2022-04-18

ion dark after only few hours of clockrun
usual recovery attempts, many detuning scans

recovers during detuning scan id22532
continue sb-monitoring clock-run

if sidebands come from 50 Hz AC mains, 80ms probe should average over 4 cycles of length 20ms?
changing to 70ms should show change, now 3.5 cycles of 50 Hz
from 06local, change to 70ms probe!?

16:42 local, change to measure +/-100Hz sideband height. keep 70ms probe.
if AC B-field at 50 Hz causes sidebands, do results support modulation-index ratios 1:2:5 for C1,2,4 Zeeman-components?

2022-04-17

20:30local ion dark
stop clockrun
all beams, clearout, 405nm
detuning scans, ion recovers, camera software stuck - restart
20:39 restart clockrun with 50Hz sideband-probing

2022-04-16

ion dark
slider pos1, all beams, clearout, 405nm on
voltages to low-EQS
detuning scans
still dark

RF off/on to empty trap.
slider pos1/OD0, all beams, 461nm, 405nm
low-EQS voltages
(461nm was left on since yesterday, unintentionally...)
16:33:00 load with 1.80A
check Rb-lock
16:44 after Rb-lock check loaded many ions.. changes between diffuse cloud or coulomb-crystal
empty trap
16:51:30 load again with 1.80A
16:56:55 two ions..
both disappear when changing V12cm from -6.5 to ca +6 V in one step, with lowered RF-drive 6Vpp
V12cm>0 gives vertical oritentation of 2-ion crystal, usual -6.5V gives horizontal orientation
back to 10Vpp RF-drive
17:00:30 load with 1.75A
17:11:50 ion, one?
slider pos1/OD1 
A counts quite low?

servo    R probe freq       B probe freq
EC1+     C1+ - 25 Hz AOM    C1+ + 25 Hz AOM
(and similar for EC1-, EC4+, EC4-, EC2+, EC2-)
Similar to low/high-EQS run these ectra servos have indexes +10, -10, +40, -40, +20, -20

2022-04-15 Good Friday

2022-04-14

lasers on, trap RF drive to 10Vpp

10:19:30Z load with 1.80A 
10:27:05 ion. PMT counts during loading ID22272 (loading-time 7min 35s)
slot2 = OD1 for 422nm
A counts 59.5 (7.4) / 2.0 (1.4) in 10ms
B counts 46.8 (7.5) / 2.6 (1.6)
C counts 24.4 (5.1) / 1.6 (1.3)   - C showed reduced counts already previously

422nm power measured with slim-sensor after beam-objective
A 0.4 uW
B 0.3 uW
C 0.3 uW

C beam better alignment gives up to 500counts/100ms (up from ca 300/100ms)

final contrasts C = -0.0309 0.0095 0.0183 RMS = 0.0371
V = [-6.5000 0.2223 23.8203 58.1454 ]
dV = -0.0256  -0.1477  0.4813

Update AHM3 model, until now we were using ab2022-01 values for all plots:
MJD0 = 59609
y0 = 2.78848e-13
y1 = -2.61147e-15

New ab2022-04 model is
MJD0 = 59669
y0 = 1.21876e-13
y1 = -2.62712e-15

comb linecenter 75.827620
+C1 peak ca 75.841209
-> abs(B) lower now 4842.8 nT ??
-C1 75.814029

low/high EQS run, 2nd try.
Insert 100ms wait after voltage change time.sleep(0.1)

low-EQS voltage is recent uMotion optimum V0=[-6.5000 0.2223 23.8203 58.1454 ]
previous high-EQS was V12_cm=0, now try even more? EMM-preserving change dV = [1.0 0 1.3 0]
high-EQS V1 = V0 + 13*dV = [ 6.5   ,  0.2223, 40.7203, 58.1454]

individual voltages, low-EQS V0
V1 = -6.7223, V2 = -6.2777, V3 = -34.325100000000006, V4 = 81.9657

high-EQS V1
cycle idx
01        V1 = -6.288966666666666, V2 = -5.844366666666667, V3 = -33.761766666666674, V4 = 82.52903333333333
02        V1 = -5.855633333333333, V2 = -5.411033333333333, V3 = -33.19843333333334, V4 = 83.09236666666666
03        V1 = -5.4223, V2 = -4.9777000000000005, V3 = -32.6351, V4 = 83.6557
04        V1 = -4.988966666666666, V2 = -4.544366666666667, V3 = -32.07176666666667, V4 = 84.21903333333333
05        V1 = -4.555633333333334, V2 = -4.111033333333334, V3 = -31.508433333333336, V4 = 84.78236666666666
...
08        V1 = -3.2556333333333334, V2 = -2.811033333333333, V3 = -29.818433333333335, V4 = 86.47236666666667
10        V1 = -2.388966666666667, V2 = -1.944366666666667, V3 = -28.69176666666667, V4 = 87.59903333333334
15        V1 = -0.2223, V2 = 0.2223, V3 = -25.875100000000003, V4 = 90.4157
21        V1 = 2.3776999999999995, V2 = 2.8223, V3 = -22.4951, V4 = 93.79570000000001
30        V1 = 6.2777, V2 = 6.7223, V3 = -17.4251, V4 = 98.8657

2022-04-12/13

Change 2" mirror on 422 breadboard to 0.5".

422 fiber coupling efficiency before modifications: laser breadboard: 730 uW, trap breadboard: 250 uW

After change Rb- error signal slightly better than before, ~2 Vpp. Similar fiber coupling efficiency.

Piezo slider installed.

2022-04-11

2022-04-09

2022-04-08 Friday

2022-04-07 Thursday

2022-04-06 Wednesday

Interleaved low/high-EQS clock-run.
12 servos, first set C1,C4,C2 using bias voltages from campaign (V0)
second set EC1, EC4, EC2 using bias voltages V1 with V12cm=0
V0 = [ -6.5, 0.2479, 23.968, 57.6641]
V1 = [ 0.0, 0.2479, 32.418, 57.6641]
EMM was measured at both voltages and is reasonably low (<10% contrast)

All servos intilized as in campaign at first.
EQS for the second set is gradually increased from V0 to V1 during the first 30 servo-cycles.
After cycle 30 second set is kept at V1.

Clockrun parameters otherwise as used in campaign:
t_probe = 80ms, OD4 filter, AOM_att = 28 dB, g1 = 1.0, g2 = 0.01, n_shots = 30
12 servos give cycle time of ca 90s.

data stored in clockrun-files for 59674 and 59675 (no other files have data from the 'E' servos)
E-servos have indexes 10, 40, 20 in the clockrun file.
            low       high
EQS-slope   28        3793  mHz/mj'-squared  (ratio 135)
EQS(5/2)    +0.095 +12.643  Hz (ratio 133)

Line-center difference after 549 servo-cycles:
df = -0.004463 (0.026016) Hz    (stdev scaled with 1/sqrt(N))
dy = -10(58)e-18

2022-04-05 Tuesday

Gaussian fits to spectra
+C1 Center =  75.841661 Height =  41.3 FWHM =  2054
-C1 Center =  75.814391 Height =  46.4 FWHM =  2012
C1 Linecenter =  75.828026 B1 estimate =  4.859030772957006
+C2 Center =  75.855176 Height =  50.1 FWHM =  1921
-C2 Center =  75.800871 Height =  42.8 FWHM =  2053
C2 Linecenter =  75.828023 B2 estimate =  4.8536505160574075
+C4 Center =  75.895847 Height =  52.5 FWHM =  1915
-C4 Center =  75.760244 Height =  46.5 FWHM =  1870
C4 Linecenter =  75.828045 B4 estimate =  4.84483786016688

popt index:   0  1  2   3
lorentzian(f, C, A, f0, g) = C + ( A / ( ( f-f0 )**2 + g ) )

FWHM = np.sqrt(popt[3])*2.0*1.0e6
center = popt[2]*1.0e6

not clear why artiq-printout and images differ? (try this also in matlab?)
artiq-fit seems to leave constant C always at zero?
images may have C>0

2022-04-04 Monday

Campaing is over:
- disable Chronograf/Slack alerts
- disable daily data-export to ftp-site (comb_data foder)

X  0.9127172
Y  0.9597931034482758
Z  1.9572068965517242

+C1 Center =  75.841600048945   FWHM =  0.0019805568136061387 Height =  47.812942893894956
-C1 Center =  75.81437703033127 FWHM =  0.0021099454037227794 Height =  46.60398837404041
C1 Linecenter =  75.82798853963814 C1 B estimate =  4.850820381716847
+C2 Center =  75.8551206600346  FWHM =  0.0020730820628837047 Height =  44.68321238122099
-C2 Center =  75.80087380303802 FWHM =  0.001693650472418099  Height =  51.66422095935006
C2 Linecenter =  75.8279972315363  C2 B estimate =  4.848426676095995
+C4 Center =  75.89594914157672 FWHM =  0.0018599360616039803 Height =  52.65380800550583
-C4 Center =  75.76015801466544 FWHM =  0.0020301402620284924 Height =  40.69441032994285
C4 Linecenter =  75.82805357812109 C4 B estimate =  4.851564603247748

2022-04-03 Sunday

ROCIT campaign

Date	Uptime	Notes
2022-04-03 Sun / 59672		clockrun continues 15:53 stop clockrun to measure uMotion, detuning-scans, seculars, spectra etc. 20:30local spectra done, continue clockrun g-ratio ca 1e6(g-1.668) = 77 noise in g-ratio ca stdev( 1e6(g-1.668) ) = 13 Prediction from email 2022-01-17 RF-drive 1e6(g-1.668) 10 Vpp 77 8 Vpp 78.8 6 Vpp 79.6 to get noise 13/sqrt(N) < 1 need to average ca 13*13 servo-cycles, about 2 hours? program RF-drive voltage decrease -1 Vpp every 2 hours first step 10 -> 9Vpp at 22 local
2022-04-02 Sat / 59671		14:39local: ion dark All 422 beams on, no 405, detuning scan (ID22059). Ion reappeared. uMotions: A: 1.4%, B: 3.1%, C: 3.5% Back to B-beam 14:53local reinitialize and restart clockrun
2022-04-01 Fri / 59670		clock-run continues
2022-03-31 Thu / 59669		clock-run continues
2022-03-30 Wed / 59668		clock-run continues 07:30local servo index 2485, ca 31 hours 11:40local ion dark 12:30local all 422 beams on (no 405), detuning scan (ID22049). Ion reappeared. umotions: A: 1.7%, B: 1.0%, C: 1.4% Back to B-beam 12:38local reinitialize and start clockrun
2022-03-29 Tuesday / 59667		clock-run continues 18:30local servo index 1446
2022-03-28 Monday / 59666		clock-run continues 17:30 local servo-index 4730 (ca 59 hours 23:47local ion dark all beams, 405nm on,1st detuning scan id22031 -> recovers (blinking because no clearout) umotion id22032 10%, id22033 11.1%, id22034 5.2% (see images for contrasts, these numbers 'histogtam constrast'?) uMotion minimizatio 20 iterations, 50kphotons id22035 ca 6+6+6 s=18 s per point V = [-6.5000 0.2468 23.9324 57.6128 ] close to last iteration? V = [-6.5000 0.2522 23.9147 57.6200 ] V = [-6.5000 0.2479 23.9680 57.6641 ] final dV = 0.0235 0.0133 0.2325 uMotion after optimization id22036, 37, 38 1.8% 1.0% 1.4% 00:21local continue clockrun went dark again?? recovery id22044 00:24 clockrun start, old servo positions
2022-03-27 Sunday / 59665		clock-run continues
2022-03-26 Saturday / 59664		ion dark, stop clockrun try to recover? id22021 recovery umotion id22022. 3. 4 05:16local start clockrun from old servo positions R-counts high (for C4+ B) - so might lock ok?
2022-03-25 Friday / 59663
2022-03-24 Thursday / 59662		ion dark recovery id22004 uMotion 6.3%, 8.2%, 2.4%, ID22005,6,7 06:12local continue clockrun, R-counts for all peaks high so should lock ok?
2022-03-23 Wednesday / 59661		ion dark in early morning 01:51Z doesn't seem to recover remotely with OD1 on 422nm also no recovery with max 422nm power (around 9 local, after ion dark for 4? hours) first loading attempt gave 2 ions second loading attempt ok uMotions 6.2, 6.7, 1.5% (ID21990,1,2) 07:27Z start clockrun with B-estimate 4.8479 uT and comb-linecenter Note higher abs(B) now ca 4.8485 uT 15:11Z ion went dark for ca 10 servo-cycles stop clockrun an recover (ID21999) 15:16Z restart clockrun with previous servo-positions I-terms seem to agree quickly, no significant settling (as seen after 07:27Z start)
2022-03-22 Tuesday / 59660		OD4/23dB/80ms spectra look reasonable, but have clear 50Hz sidebands and weaker 100Hz sidebands. C1-pair measured with both 50Hz sidebands visible, C2 only one side visible, C4 not measured uMotions <5% 10:25local restart 80ms clockrun with revised B-estimate 4.484 uT 10:46local servo-index >25, all excitations >50/300 (similar to previous clock-runs) Dsum ok (doesn't diverge, stays <10 Hz) B1, B2, B4 consistent ca 4.8478 uT 11:33 one hour of data. self-comparison looks ok. eqs-slope +0.023 Hz. 1e6*(g-1.668) = 76, similar to previous runs +0.179 Hz relative to AHM3 model
2022-03-21 Monday / 59659		no clockrun data :( linewidth/coherence problems related to either(both?): - minus-k not floating - pdh-detector tilted spectra now look better, drift settles slowly
2022-03-20 Sunday / 59658		no clockrun data :(
2022-03-19 Saturday / 59657		various clock-laser tests OD0 0.2, 0.4, 0.8us spectra look ok, FWHM close to Fourier limit OD2 2ms spectra ok:ish 15local start OD2/18dB/1.5ms clock-run Note 18 dB AOM attenuation, so more AOM-chirp than previously? beam is B, dark/bright threshold now 10 cycle time ca 16.8s with n_shots=30 excitation probabilities from 2 hours of 1.5ms clockrun ZC pR pB +1 24.26 24.26 -1 21.63 21.80 +2 22.78 22.78 -2 25.14 25.10 +4 22.30 22.30 -4 24.60 24.58 19local stop clockrun to measure spectra 18dB 1.5ms 23dB 3.0ms 28dB 6.0ms
2022-03-17 Thursday / 59655		Work with PDH-lock and possible RAM or electrical feedthrough of 25 MHz EOM signal to PDH-detector While waiting for cavity to settle: 15:19local try OD4/18dB/20ms clock-run C1 was maybe locked, others not, Dsum diverges 15:31 restart 15:59 restart 17:00 restart 17:30 close cavity door 17:46 restart with OD4/18dB/15ms to see if p_exc changes with 15ms instead of 20ms probe? after 30 servocycles p_exc looks similar or slightly worse compared to 20ms run 20 ion dark all beams, 405nm, detuning scan ID21738 is revival detuning scan (405nm off, but 405nm during several scans prior to this) 20:14 continue with OD4/23dB/40ms clockrun - laser drift still 100 mHz/s, B from 20ms clockrun now 4.841 uT? p_exc ca 27/300 = ca 10% 21:52 driftcomp now active, drift < 50 mHz/s start OD4/28dB/80ms clockrun p_exc low, dsum not ok.. stop clockrun spectra tomorrow when drift settled..
2022-03-16 Wednesday / 59654		07:10Z ion dark, no recovery with usual procedures to full 422nm power -> ion recovers! (was dark from ca 19 local yesterday!?) to OD1 filter for 422nm uMotion 1.4%, 3.5%, 3.9% (ID21632,3,4) ID21636 is B-beam detuning scan ID21637 repeat 07:14Z start clockrun, 90ms probe, 28dB DDS att, OD4, PMT threshold now 5 after 20 servo-cycles highes p_exc ca 20/300 = 7% ID21642 spectrum, OD4/28dB/80ms, 120 Hz span, 1 Hz step No clocrun data from today :(
2022-03-15 Tuesday / 59653		5:05Z: Stop clock-run. ID21556: OD4, 28 dB, 80 ms probe peak search (to check if changing PDH-cables had any effect), 1 Hz step, 110 Hz span, 5 Hz Fourier limit (AOM). ~07:40: Start service break for improved 422nm collimator/Fiber Measure coupling efficient for 422 before modifications: At fiber collimator on laser breadboard (no OD-filter): 750 uW At trap breadboard after collimator: 250 uW Replaced old collimator with f = 7.5 mm (4.6 mm had too small beam). Coupling efficiency is similar (750 -> 250 uW) Found issue where first shot of n_shots always was a bright state. This is because coolinglaser and repumper were left permanently ON after the n_shots loop. Fix by removing cooling+repumper ON-statements at end of loop. 13:50Z fix issue with always bright state on first shot. Lot's of laser-drift, so difficult to get clock-run going and low excitation-counts 13:59Z restart with updated comb-linecenter/B - driftcomp now active but lags behind true cavity drift 14:43 restart again, p_exc seems low? set new bright/dark threshold based on 10ms counts: threshold = 5 (was 15) 16:15Z possibly higher p_exc with 90ms probe? 16:20Z try 100ms clockrun? cycle-time ca 52.2s with n_shots=30 tried intra-cavity power stabilization servo, set-point is 3.5V on cavity-transmission detector back to intra-cavity servo off, cavity-transmission detector now ca 4.3 V 16:32 try 90ms and 26 dB AOM attenuation? 16:56Z back to original settings OD4/28dB/80 ms -> excitation only 25/300 17:34Z restart with 90ms ion dark id21604 recover from dark ion? all beams, 405nm still dark, leaave pmt monitor
2022-03-14 Monday / 59652		ca03:30 local, ion dark, stop clockrun (no recovery with 405nm on during clockrun) ion recovers with all beams, clearout, 405nm - no detuning scans required restart clockrun 16local stop clock-run to replace PDH-detector, EOM-drive cables. uMotion 2.2%, 1.5%, 2.7% (measurements 21546, 21547, 21548) PDH-lock on again, -21.2 dBm LO drive from Toptica, LO-angle optimum now ca 154 degrees 674nm power - at corner, before EOM, 26 uW - into cavity 19.5 uW PDH-detector 1.5 VDC not locked, down to 1.1 VDC when locked (2 mV when dark) - 0.4/1.5 = 27% drop If 50% in carrier, 25+25% in sidebands, ideally expect DC-level to drop 50% (?) - we see 27/50, so couple 53% of carrier into cavity 27%*19.5 uW = 5.27uW carrier into (and out) of cavity Transmitted power detector 110 kOhm transimpedance, 0.36 A/W responsivity Expected transmitted detector signal 5.3 uW * 0.36 A/W * 110 kV/A = 0.2 V? (17.5-fold too little compared to experiment?) We see 3.5 VDC on detector -> 3.5 V / 100kV/A / 0.36 A/W = 88 uW? (16.6-fold too much, compared to Thorlabs power-meter reading) 16:30local close cavity doors 16:52local start clockrun with new comb-linecenter and previous B4 estimate HOX: fiber-noise servo must be restarted off/on, after clock-laser has been unlocked or off 17:00 reboot fiber-noise servo -> now get quantum jumps as expected PMT-counts drop quite low due to temperature swings Cavity frequency ca +3 kHz after working with cables etc
2022-03-13 Sunday / 59651		ca 15:30local load new ion minimize micromotion dV = 0.0007 -0.0333 0.4846 V = [-6.5000 0.2389 24.0884 57.3503 ] uMotion 1.9%, 2.0%, 1.6% (ID 21530,1,2) 16:08local start clockrun -> Dsum diverges? 16:16 restart with comb-linecenter and Best 4.84421 uT (remove expanded FWHM probing-points from start of clock-run) C1, C2 ok? C4 not locked B1 4.8448, B2 4.8449 16:21 restart with B2-estimate Dsum seems better now, all peak-servos give ok R/B counts 16:29local index 10: C1 average excitation seems normal 50 jumps / 10*30 probes = 17% C2 and C4 still low exc-prob. Dsum OK. 16:33Z clockrun restarted, beam used previously today was C - now changed to B as usual.. better idea for initial convergence of clock run? - start with only C1, run 10(?) servo-cycles to see that they are locked (C1-linecenter close to comb, and B1 resonable) - add C2, run further 10 (?) servo-cycles to see that C2-linecenter and B2 agrees - finally add C4 servos, with now accurate B2 estimate?
2022-03-12 Saturday / 59650		Ion dark at 10:58Z All beams on, 405 on, detuning scans.. ion probably lost
2022-03-11 Friday / 59649		id21436 detuning scan, all beams and 405nm - still dark id21437 detuning scan,, 405nm off id21439 repeat with 405nm on Check 422 OK, no ion visible still. 18:33Z: Try to load, 1.75 A. Ion after ~20min. Probably double, since umotions are 50%. 19:00Z: Try to load again, 1.75A. Ion! after 10 min. Set detuning back to 208 MHz, and OD filter to 0.9. uMotions: A: 6%, B: 6%, C: 6%. ID21469: Detuning scan with B-beam Tried to start clock-run, counts not too good. Leave B-beam on, and leave lab to let things settle. Leave lab at 19:17Z Start clockrun at 20:06Z.
2022-03-10 Thursday / 59648		08Z ongoing continuous clockrun since yesterday 21425 detuning scan to wake up ion, all beams and 405nm 11:19local uMotion 5.2%, 5.6%, 5.3% (21427,8,9) 21431 B-beam detuning scan B-counts 116.6 (9.2) / 0.6 (0.9) in 10 ms 11:22 local restart clockrun (no changes to parameters) 11:38 servo-cycle nr20, initial FWHM-shrink done.
2022-03-09 Wednesday / 59647		ion dark ca 05:00Z recovers during detuning scan 21414 (no 405nm) - with all beams, after 405nm was on for a while 05:37Z uMotion 4.5%, 5.3%, 5.1% (21416, 21417, 21418) B-beam detuning scan 21420 clockrun restarted ca 05:40Z data looks valid from 06:00Z ca 14Z sudden jump in B-field of +0.2 nT seen also in servo I-terms as jumps in different directions, followed by (slow) convergence
2022-03-08 Tuesday / 59646		clockrun ongoing, looks ok 14:40Z restart with increased n_shots=30, based on looking at jump-statistics and binomial distribution Previous excitation probabilities gave ca 30% zero-jumps with n_shots=10 New n_shots=30 should give 10-fold less 0-counts, ca 3% statistics for 59645 (invalid points removed, ca 5730 servo-cycles valid) +pR +pB -pR -pB C1 0.135618 0.135560 0.151910 0.154135 C2 0.177879 0.177774 0.153846 0.152224 C4 0.156620 0.157335 0.139375 0.139421 excitation-probability not expected to change with n_shots=30, but statistics for discriminant improved? ca 720 servo-cycles from 14:40Z restart to UTC-midnight (720*45s = 9 hours) all excitation probabilities are slightly higher +pR +pB -pR -pB C1 0.145245 0.144645 0.167128 0.165466 C2 0.188412 0.188735 0.167359 0.167545 C4 0.173675 0.173859 0.148870 0.151083
2022-03-07 Monday / 59645		09:00Z clockrun ongoing, looks ok No visits to lab -> lab temperature stable Longer Ion dark moment around 19:45Z (index 5793) - but ion recovers during clock-run (no manual intervention) recovers 5 minutes later 19:50Z (index 5813)
2022-03-06 Sunday / 59644		2022-03-06T19:00 ion went dark, end of servo-cycle 8912. Last valid cycle 8911 19:31Z uMotion 4.0%, 4.1%, 4.2% (IDs 21401, 21402, 21403) 19:33Z B-beam detuning scan ID 21405 ARTIQ clockrun program revised to store jump counts in 2nd detection window also store also eqs52=(10/3)*eqs_slope 19:36Z clockrun restarted 19:45Z data looks ok
2022-03-05 Saturday / 59643		Ion fluorescence recovers with all beams, clearout, 405nm, and detuning scan B-beam detuning scan ID21386 05:27Z uMotion 3.5%, 3.0%, 2.6% (IDs 21387, 21388, 21389) 06:00Z clockrun restarted, Dsum ok
2022-03-04 Friday / 59642		Coil currents from 2022-01-25: I(-34deg) = [-0.0408 -11.4939 -0.7741] mA 2022-02-18 has coil current measurements (artiq set-point, set-point as displayed on box display, and DMM measurement) 80ms spectra RID21340 OD0 rabiflops (but unsure about 674nm power-stabilization..) uMotion minimization ID21341, V = [-6.5000 0.2382 24.1217 56.8657 ] 12:46Z uMotion: 1.7%, 0.6%, 0.8% (IDs 21342, 21343, 21344) From ca 17:45local 80ms clockrun with OD4/28dB Zeeman AOM attenuation n_shots=10, g1=1.0, g2=0.01, Zeeman pair order C1, C4, C2 Zeeman shift coeffiecents used currently in artiq: Z1 5.6120442464394 Z2 11.1885484963681 Z4 27.9891412391756 Ion went dark 2022-03-04T22:09 (-C4 peak, index 1568) Last valid servo-index 1567

2022-03-29 Tue

2022-03-28 Mon

2022-03-27 Sun

2022-03-26 Sat

2022-03-24

2022-03-23

2022-03-22

2022-03-21

2022-03-20

     B-beam        A-beam        C-beam
ZC   Height FWHM   Height FWHM   Height FWHM
+1   36.7    318   8.3     344   20.1    352
-1   33.1    397   9.4     332   51.8    335
+2   32.8    372   7.2     341   40.5    341
-2   33.3    398   5.7     326   17.4    341
+4   34.3    348   11.5    209   23.8    357
-4   31.3    403   5.9     365   12.1    298

ZC  Height FWHM freq
+1  33.6   389  75.84218945598637
-1  36.2   352  75.81500590050898
 

ZC  Height  FWHM  freq
+1  40.0     359  75.842173557124
-1  37.6     309  75.81502638235217

ZC  Height  FWHM  freq
+1  36.4     383  75.84219016431294
-1  29.5     388  75.82860247400467

2022-03-19

    18dB/200us    23dB/400us    28dB/800us    OD2/18dB/2ms
ZC  Height FWHM   Height FWHM   Height FWHM   Height FWHM
+1  49.8   1986   47.9    972   34.7   541    31.5   346
-1  40.8   2020   41.6    970   30.9   554    24.8   315
+2  41.7   2014   38.2    976   25.5   624    
-2  52.7   1937   50.2    945   42.1   552
+4  44.1   1989   46.6    936   29.4   577
-4  53.2   1919   52.3    988   44.1   447

800us +C1 Center =  75.84217488955069
800us -C1 Center =  75.81502686778107
2ms +C1 Center =  75.84218164469243
2ms -C1 Center =  75.8149971315586

Fourier limit 0.5*0.8/1.5ms = 267 Hz AOM
ZC  height  FWHM
+1  34.1    360
-1  32.4    331
+2  34.7    358
-2  38.5    322
+4  34.1    332
-4  34.7    347

 
Fourier limit 0.5*0.8/3ms = 133 Hz AOM
ZC  height  FWHM
+1  25.0    287
-1  19.7    318
+2  20.4    315
-2  25.1    296
+4  22.1    300 
-4  24.3    313

Fourier limit 0.5*0.8/6ms = 67 Hz AOM

2022-03-18

2022-03-17

2022-03-16

PDH-detector signal measured through 11 dB coupler
50 Ohm terminated shows 50-53 mV AC RMS on oscilloscope
11 dB is 12.6-ratio for power, sqrt(12.6)=3.55 ratio for amplitude
Photodetector output is 3.55*50 = 177 mV AC RMS - should not be close to saturation?

Try increasing driftcomp-AOM attenuation to 22 dB, this lowers cavity transmission from 4.5V to 2.2V

comb linecenter 75 827 873
+C1 75 841 522, Height =  37.6, FWHM 1915
-C1 75 814 273, Height =  55.9, FWHM 1814
C1 Linecenter =  75.82789708424843, B1 estimate =  4.855455434463197

 
comb linecenter 75 827 870
+C1  75 841 459, Height =  34.4, FWHM 714
-C1  75 814 306, Height =  50.2, FWHM 679
C1 Linecenter =  75 827 882, B1 estimate =  4.838311553162914

comb linecenter 75 827 867
+C1 75 841 449, Height =  34.9, FWHM =  233  
-C1 75 814 288, Height =  46.4, FWHM =  257
C1 Linecenter =  75 827 868, B1 estimate =  4.839806628910559

comb linecenter 75 827 864
+C1 75 841 439, Height =  16.6, FWHM =  197  (not close to Fourier limit anymore...)
-C1 75 814 267, Height =  27.1, FWHM =  194
C1 Linecenter =  75 827 853, B1 estimate =  4.8418711643831935

+C1 FWHM 217
-C1 FWHM -

2022-03-15

+C1 Center =  75.8527774548399,  height 49.6, FWHM 1886
-C1 Center =  75.82563369416457, height 43.5, FWHM 1974
B1 estimate =  4.836697553222443

2022-03-14

2022-03-13

2022-03-12

2022-03-10

2022-03-09

2022-03-08

2022-03-06

2022-03-05

2022-03-04

+C1 height 27.8, FWHM 5.33 Hz AOM
-C1 height 34.4, fwhm 5.48 Hz AOM
B1 estimate =  4.843143976250383
+C2 height 37.4, FWHM 5.76 Hz AOM
-C2 height 26.2, FWHM 5.72 Hz AOM
B2 estimate =  4.843154264903667

probe   +C1 max count
ms

60      23
70      26
75      30
80      39 (outlier?)
85      33
90      31
100     29

2022-03-03

5Hz AOM step, optical 50 Hz sidebands at 5 steps from carrier?

+C1 FWHM 99 Hz AOM (sidebands?)
-C1 90 Hz
B1 estimate =  4.842979170129967

B4 estimate =  4.842658064145234

PA output DDS off  -43 dBm
PA output DDS on   +27.9 dBm     (2022-01-27 measurement has -3 dB less: +24.8 dBm)
ARTIQ attenuation 18 dB -> output measures -6.3 dBm
-> PA gain 27.9 - (-6.3) = 34.2 dB
AMPA-B-30 spec >33 dB gain

ARTIQ attenuation 0 dB -> output measures +10.5 dBm
back to 18 dB attenuation -> measures -6.3 dBm

based on 2022-01-27 measurements:
ARTIQ att.    ARTIQ output   PA-output
18            -8.2           +24.9 dBm    (measured values)


ARTIQ att     B-beam thru chamber P_674
28            90 nW, background 22 nW
26            179 nW bg 21 nw
24            364 nW bg 21 nW
22            715 nW bg 21 nW
20            1.25 uW bg 13 nW
18            1.83 uW bg 13 nW

NOTE: when AOM kept on for several seconds, some time-dependence of P674 !? AOM chirp/heating effect?

+C1 Center =  75.85334737929657, Height =  43.1, FWHM =  1920
-C1 Center =  75.82608352850822, Height =  44.3, FWHM =  2075
B1 estimate =  4.85809619295892

Zeeman AOM adjustments

before adjustments, 674nm power at B-beam output through chamber
18 dB DDS attenuation
AOM off 0.02 uW - AOM on 1.95 uW

Before AOM-cube, with trap-breadboard intensity servo set-point 3.68V - ca 60 uW
before B-beam cube ca 23 uW (double-pass AOM efficiency 23/60 = 38%)
  power split into 3 for A, B, C beams
before A-fiber 5.2 uW
before B-fiber 6.7 uW
before C-fiber 8.5 uW
 (sum of these 20.4 uW    loss-beam at B-cube 0.4 uW   some loss in dichro that joins 422nm and 674nm also)

after adjustments still 1.9 uW at B-beam output through chamber

2022-03-02

+C1 Center =  75.85328806307895, Height =  29.6, FWHM =  366
-C1 print:Center =  75.82610870579471, print:Height =  48.120204741294884, print:FWHM =  0.0003301814701812016
print:C1 Linecenter =  75.83969838443683, print:B1 estimate =  4.843040448493246

+C1 Center =  75.85331037205954, Height =  40.7, FWHM =  1488
-C1 Center =  75.8261581589811,  Height =  53.1, FWHM =  1579
C1 Linecenter =  75.83973426552032, B1 estimate =  4.838203671623676

+C1 FWHM 340 Hz AOM
-C1 FWHM 352 Hz
+C2 FWHM 329 Hz
-C2 

comb linecenter 75 849 657 (start of run)
+C1 75 853 275,  height 41.1, FWHM 928 (Gaussian fit doesn't fit rabi-sidebands..)
-C1 height 57.8, FWHM 966
C1 Linecenter =  75.83968368838535 B1 estimate =  4.843499657984703
+C2 height 51.1, FWHM 948
-C2 height 36.3, FWHM 890
C2 Linecenter =  75.83967475362617 B2 estimate =  4.846489510685067
+C4 height 48.8, FWHM 959
-C4 height 35.1, FWHM 952
C4 Linecenter =  75.83971115161137 B4 estimate =  4.844432784122737

2022-03-01

Check secular frequencies with tickler
x search 0.90-0.91 MHz, 15 dB attenuation, B-beam -> peak ca 0.909 ?
y search 0.95-0.96 MHz, 15 dB attenuation -> weak resonance 0.956 MHz? try 12 dB attenuation
z search 1.94-1.95 MHz, 26 dB, B-beam -> 1.9485 MHz

    resonance (FWHM) Hz
    A-beam               B-beam             C-beam
X   909262.9 (500.2)     909205.0 (419.7)   909259.9 (520.3)    (measurement order B, A, C)
Y   956179.5 (1288.2)    956299.7 (800.5)   956308.5 (777.4)    (order A, B, C)
Z   1948544.0 (310.0)    1948500.6 (854.2)  1948525.4 (447.7)   (order A, B, C)

cooling-rate proportional to scattering rate?
A counts 9305.8 bright / 62.6 dark in 1000ms
B counts 8058.8 bright / 48.0 dark
C counts 6620.4 bright / 76.0 dark

+C1 FWHM 312 Hz AOM (central feature narrower, sidebands on each side?)
-C1 318 Hz

Toptica PDH settings: channel2, 25 MHz, -24.2 dBm (40 mVpp), input level -10 dBm, lock level 0V, phase 315 degrees

+C1 FWHM 312 Hz AOM
-C1 292 Hz
B1 estimate =  4.847911109194807
+C2 336 Hz
-C2 380 Hz
B2 estimate =  4.844192617677165
+C4 399 Hz
-C4 329 Hz
B4 estimate =  4.845883965614396

2022-02-28

2022-02-27

Fourier limit 20 Hz optical, 10 Hz AOM
    FWHM AOM
+C1 220 Hz
-C1 214 Hz
+C2 238 Hz
-C2 250 Hz
+C4 248 Hz
-C4 263 Hz
B4 estimate =  4.844944644042546

2022-02-26

2022-02-25

+C1 FWHM 296 Hz
-C1 295 Hz
B1 estimate =  4.844254243956416
+C2 342 Hz
-C2 291 Hz  (more input gain, slightly less main-gain for this peak)
B2 estimate =  4.8471796451916385
+C4 329 Hz
-C4 308 Hz
B4 estimate =  4.846315478829265

PDH settings with no mini-circ amplifier on PDH-detector
ULI: fastest, SLI: 3, FLD: 7, FLI: 8
main-gain ca 2.5
no attenuator on ECDL current control cable

PDH settings with mini-circ amplifier (10dB attenuator after detector, before mini-circ amplifier)
16dB attenuation on ECDL current control
ULI: 100V/s/V, SLI off, FLD 6, FLI: 8
main-gain 4

2022-02-24

+C1 Center =  75.85317005690537, Height =  32.4, FWHM =  249
-C1 Center =  75.82592917944645, Height =  38.4, FWHM =  230
C1 Linecenter =  75.83954961817591, B1 estimate =  4.854002616997453

2.5ms probe gives 160 Hz AOM Fourier limit

comb linecenter 75 839 525 (start of run)
+C1 Center =  75.85317034677945, Height =  32.1, FWHM =  225
-C1 Center =  75.82592562351964, Height =  22.0, FWHM =  273
C1 Linecenter =  75 839 548, B1 estimate =  4.854688
+C2 Center =  75.86670286208648, Height =  25.2, FWHM =  244
-C2 Center =  75.81237696790912, Height =  28.7, FWHM =  268
C2 Linecenter =  75 839 540, B2 estimate =  4.855491
+C4 Center =  75.90749916601803, Height =  26.9, FWHM =  233
-C4 print:Center =  75.77159753708638, print:Height =  26.73811334304485, print:FWHM =  0.0002828593188409724
C4 Linecenter =  75.8395483515522, B4 estimate =  4.855513
comb linecenter 75 839 533 (end of run)

comb linecenter 75 839 513 (start of run)
Fourier limit 160 Hz AOM
+C1 Center      75 853 134, Height =  28.1, FWHM =  244
-C1 Center      75 825 882, Height =  23.2, FWHM =  344  (more activity in lab - disturbance or not??)
C1 Linecenter   75 839 508, B1 = 4.856092
+C2 Center      75 866 646, Height =  41.4, FWHM =  254
-C2 Center      75 812 347, Height =  9.4,  FWHM =  277
C2 Linecenter   75 839 497, B2 = 4.853101
+C4 Center      75 907 385, Height = 25.6,  FWHM =  237
-C4 print:Center =  75.77155583401284, print:Height =  8.175377539725075, print:FWHM =  0.00021086636619431357
C4 Linecenter   75 839 471, B4 = 4.852934
comb linecenter 75 839 476 (end of run)

comb linecenter 75 849 516 (start of run)
+C1  =  75.853119 

comb linecenter 75 839 511
+C1 Center      75 853 169, Height =  31.5, FWHM =  896
-C1 Center      75 825 886, Height =  55.7, FWHM =  921
C1 Linecenter   75 839 527, B1 = 4.861601
+C2 Center      75 866 635, Height =  49.5, FWHM =  1033
-C2 Center      75 812 396, Height =  36.1, FWHM =  994
C2 Linecenter   75 839 515  B2 = 4.847667
+C4 Center      75 907 418, Height =  41.8, FWHM =  891
-C4 Center      75 771 562, Height =  30.0, FWHM =  988
C4 Linecenter   75 839 490, B4 = 4.853862
comb linecenter 75 839 517 (end of run)

+C1 fit to noisy data gives FWHM 178 Hz (similar to 40ms spectrum earlier)
-C1 FWHM 165 Hz
B1 estimate =  4.851566097194596

Initialized with last B-estimate 4.871905 uT - but now B seems lower?
peaks offset by maybe 1/4th of span, 150 Hz optical, so B should be adjusted ca -30 nT (assuming ca 5 Hz/nT for C1) -> 4.84 uT

+C1 fit to broad noise peak, Center =  75 853 123, FWHM 170 Hz AOM
-C1  Center =  75.82588931631606, FWHM 163 Hz
B1 estimate =  4.852793995323336
B2 estimate =  4.852588307569552

2022-02-23

PDH signal as measured by photodiode, around 25 MHz EOM modulation frequency. Laser locked.
Measured through 11 dB coupler

Yellow: signal from photodetector
Red: original configuration with one mini-circ +28 dB amplifier (some compression maybe?)
Blue: signal after various tests and improvements - both high-pass and low-pass filters to keep 25 MHz signal but attenuate 50MHz and close to DC
SHP-20 high-pass filter
BPL-30 low-pass filter (seems strong 50 MHz component was causing amplifier saturation before this filter was added, after photodetector, before mini-circ amplifier)

PDH error signal
servo-bumps at ca -50 dBm (measured at photodetector output, with 11 dB coupler) -> signal at -39 dBm

mini-circ ZFL-500LN gain at +15V is +28 dB

with two minicircs PDH photodetector spectrum doesn't seem any higher??

SHP-20 high-pass filter tried on photodetector output, removes 0-1 MHz frequency content of photodetector.
SHP-20 has large group delay at 25 MHz (not ideal?), Toptica PDH mixing angle ca 190 degrees now?
27.87ns group delay, period is 1/25MHz = 40 ns -> 251 degrees !?

Try to increase PDH error signal, filters to block DC-2MHz and also 50 MHz!

2022-02-22

+C1 FWHM 292 Hz
-C1 FWHM 249
B1 estimate =  4.867662494842605
+C2 268 Hz
-C2 268 Hz
B2 estimate =  4.870678084197625
+C4 286 Hz
-C4 289 Hz
B4 estimate =  4.871904886216983

FALC settings 2022-02-22 ca 14 local:
ULI 20 (V/s)/V
SLI pos 7: 50 Hz - 3 kHz (lock first with FLI, then turn on SLI)
FLD pos 7: 190k - 1MHz
FLI pos 8: 6k5 - 80kHz
output 20 dB attenuator
main-gain trimpot ca "4"

Toptica
EOM drive level -24.2 dBm
Input level 0 dBm
Lock level +0.073 V
Phase 12.9 degrees

2022-02-21

Fourier limit 250 Hz AOM: 
+C1 267 Hz
-C1 297 Hz
+C2 269 Hz 
-C2 246 Hz
+C4 292 Hz
-C4 298 Hz
B4 4.87268 uT (was typo "2.87.."?)

2022-02-20

FALC settings from 2022-02-19
SLI pos 6: 110 Hz - 6.5 kHz
FLD pos 7: 190 kHz - 1 MHz
FLI pos 8: 6.5 kHz - 80 kHz
ULI pos 1on, 4on: 100 (V/s)/V   Fine-1 ARC-factor -1 V/V

2022-02-19

RF-drive   min B-contrast when scanning V12diff
9.9        17 %   id20643
9.8        11 %   id20644
9.7        10 %   id20645
9.6        10 %   id20646
9.5        11 %   id20647
9.4        13 %   id20648
9.3        16 %   id20649
9.2        17 %   id20650

2022-02-18

+C1 75 853 327, height 38.6, FWHM 302, Fourier limit 250 Hz AOM
-C1 75 826 047, height 40.8, FWHM 281
C1 75 839 687, B1 4.861081
+C2 75 866 894, height 43.5, FWHM 274
-C2 75 812 486, height 33.4, FWHM 345
C2 75 839 690, B2 4.862868
+C4 75 907 746, height 32.2, FWHM 291, (far right in scan)
-C4 75 771 625, height 36.2, FWHM 290
C4 75 839 685, B4 4.863354
comb linecenter 75 839 682

+C1 75 853 363, height 40.9, FWHM 472, Fourier limit 500 Hz AOM
-C1 75 826 030, height 48.2, FWHM 444
C1 75 839 697, B1 4.870498
+C2 75 866 697, height 40.0, FWHM 498
-C2 75 812 487, height 36.2, FWHM 461
C2 75 839 691, B2 4.862817
+C4 75 907 728, height 38.7, FWHM 499
-C4 75 771 642, height 41.7, FWHM 419
C4 75 839 690, B4 4.862455

comb linecenter 75 839 687
+C1 75 853 365, height 45.9, FWHM 921
-C1 75 826 068, height 41.1, FWHM 921 
C1 75 839 717, B1 4.86392

Seculars 2022-02-18, 10Vpp RF-drive, Vbias = [-6.5 0.0273 23.7568 56.5703]

Z 1.939298  (repeat 1.939265 )
Y 0.951322  (repeat 0.951240 )  camera image blurry but no clear side-side movement, height <0.2
X 0.903902  (repeat 0.903876 )

Try Nelder-Mead uMotion optimizer:
1st run contrasts: C = -0.1875 -0.2036 -0.1363 RMS = 0.3085  
2nd run V = [-6.0000 -0.0728 24.0370 56.7160 C = -0.1515 -0.0956 -0.1246 RMS = 0.2182

Lower RF-drive to 9.7V and run optimization again
3rd run, 100k photons, n_iterations=20
V = [-6.0000 0.0375 24.3179 56.8077 ]   C = -0.1603 -0.1043 0.1746 RMS = 0.2590

Try V12cm = -6.5 ?
4th run, 50k photons, 10 iterations
V = [-6.5000 0.0625 24.3000 57.3080 ]   C = -0.3672 -0.1260 -0.1409 RMS = 0.4130

Set RF to 9.4V
5th run, 50 kphotons, 10 iterations
V = [-6.5000 0.0273 23.7568 56.5703 ]  C = -0.1452 -0.1378 -0.1881 RMS = 0.2747

Bias voltage measurements:
adjust V1 and V2 to zero - while keeping ion in trap.

Setpoint    measured
V1=0        V1=1.13(1) mV
V12cm=-2V   V1 = -1.99872(1) V  V2 = 1.99874 V

ramp down V34cm in steps of 2V, and V34diff in steps of 5V -> this keeps ion trapped but camera image is blurry
Setpoint                  measured
V34cm=0, V34diff=0        V3 = +0.0026(16) V   V4 = +0.0024(17) V
V34cm=0, V34diff=55       V3 = -54.9980(16) V  V4 = +55.0038(17) V
V34cm=27, V34diff=55      V3 = -27.9986 V      V4 = +82.0030(17) V

V12cm = -6                V1 = -5.9989 V       V2 = -5.99937(1) V 

Coil current measurements (mA):
I1: Reading:  -0.0413, set-point: -0.04080, DMM-measurement:  -0.0384
I2: Reading: -11.4941, set-point: -11.4939, DMM-measurement: -11.490
I3: Reading:  -0.7749, set-point: -0.77410, DMM-measurement:  -0.7678

2022-02-17

Try new uMotion optimizaiton with scipy.optimize.minimize( method='Nelder-Mead' )

First run
C = -0.3262 0.0710 -0.0561 RMS = 0.3386    at voltages [-0.0022, 23.6312, 56,9558]

Second run
print:C = 0.0606 -0.0654 -0.0422 RMS = 0.0987

repeated contrasts
C = -0.6464 -0.5158 -0.3178
C = -0.6413 -0.5400 -0.3960
C = -0.6197 -0.5084 -0.3581
C = -0.6199 -0.5190 -0.3378
C = -0.6397 -0.4739 -0.3023
C = -0.6200 -0.4581 -0.2982
C = -0.6168 -0.4594 -0.2775

-6.51, -6.38, -6.81, -5.76, 

+2.23
+6.75
+3.79
+4.39
+1.35
+4.67
+1.15
+2.5
+2.05
+1.83

Repeated measurement of the same uMotion contrasts - without changing trap voltages:

C = 0.1271 -0.1746 0.0968
C = 0.1333 0.1077 0.1054
C = 0.1112 -0.1625 0.0930
C = 0.1122 -0.1583 0.0853
C = 0.1252 0.1278 0.1337
C = 0.0949 0.1459 0.1042
C = 0.0873 0.1324 0.0782
C = 0.1021 -0.1509 0.0865

2022-02-16

comb linecenter 75 839 357
+C1 75 852 918, height 30.5, FWHM 311 (Fourier limit 133 Hz AOM!?)
-C1 75 825 805, height 32.3, FWHM 367
C1  75 839 362, B1 4.8313 uT
+C2 75 866 379, height 39.9, FWHM 271
-C2 75 812 331, height 29.3, FWHM 354
C2  75 839 355, B2 4.8306 uT
-C4 75 906 925, height 32.5, FWHM 328
+C4 75 711 790, height 31.1, FWHM 287
C4 75 839 357, B4 4.82813 uT
comb linecenter 75 839 357 (end of run)

past B-estimate 4.827 uT
comb linecenter 75 839 356
+C1 75 852 912, height 44.3, FWHM 974
-C1 75 825 828, height 48.9, FWHM 1030
C1 75 839 370,  B1 4.826 uT

2022-02-15

+C1 75 852 910, height 23.8, FWHM 241 (Fourier limit 133 Hz AOM)
-C1 75 825 810. height 25.6, FWHM 247
C1 75 839 360, B1 4.8288398
+C2 75 866 369, height 31.9, FWHM 203
-C2 75 812 362. height 26.5, FWHM 239
C2 75 839 365,  B2 4.8269495
+C4 fit fails, peak to right of scan range 
-C4
C4 

comb linecenter 75 839 353 (start of run)

+C1 75 852 937, height 41.1, FWHM  934
-C1 75 825 778, height 40.2, FWHM 1060
C1  75 839 274  B1 4.83927 uT   (old estimate was 4.80587)
+C2 75 866 377, height 46.4, FWHM  972
-C2 75 812 294, height 43.6, FWHM 1042
C2  75 839 336, B2 4.833757
+C4 75 906 947, height 48.9, FWHM 1018
-C4 75 771 707, height 42.5, FWHM  992
C4 75 839 372   B4 4.8286595

comb linecenter 75 839 356 (end of run)

Adjust FALC gains and offsets to use both SLI and FLI integrators - this should raise gain at low frequencies.
Using SLI requires input offset to be trimmed with SLI on.
Using SLI also requires ULI-offset to be trimmed correctly.

2022-02-14

DDS mixer frequency for comb-counter channel2
Nominal 215 MHz
ARTIQ reports tuning word 60517119992791 corresponding to 214999999.999999850988
if this is true, difference between nominal and actual -0.000000149012 Hz

DDS_output = 1 GHz * FTW / 2^48

However past AD9912 measurements show tuning-word is always even!
With 60517119992791-1 we get  actual-nominal= -0.000003695488
with 60517119992791+1 we get  actual-nominal= +0.000003397465

Comb data f1+f2 sum from weekend shows a sum of:
Saturday +0.00333  mHz 
Sunday   +0.003892 mHz

beatnote f1 ca -15.5 MHz
beatnote f2 ca +234.5 MHz
Mixing frequency for f2 215 MHz -> SDR measures 234.5-215 = 19.5 MHz

SDR computes f1+f2 sum as:
f1 + f2 + 215 MHz
we observe +3 uHz error here, so actual mixing frequency is lower than nominal: FTW-1 row above!?
FTW = 60517119992791-1 -> mixing-frequency is 214999999.999996304512
Try using this in SDR data processing from now on! 

New AHM3 model from Atomic Bulletin 2022-02
# ab 2022-01 AHM3
MJD0 = 59579
y0 = 3.57713e-13
y1 = -2.59867e-15

# ab 2022-01 AHM3
MJD0 = 59609 
y0 = 2.78848e-13
y1 = -2.61147e-15

Change in predicted frequency for 59624 (2022-02-14)
y_AHM3(ab2022-01, 59624) = 2.4077285e-13
y_AHM3(ab2022-02, 59624) = 2.3967595e-13
difference  -1.096899999999993e-15   (less than half a day of drift)

2022-02-11

Notes on EOM PA drive level:
PA is mini-circ ZHL-5W-1, nominal gain 40 dB (acual ca 45.5 dB from datasheet, +24VDC supply), +37dBm output @ 1 dB compression

Toptica source     Measured -50dB dummyload-monitor   Actual PA output(+50 dB from measurement)   measured gain

-6.2 dBm           -11.5                              +38.5                                       44.7
-9.2 dBm           -14.2                              +35.8                                       45
-12.2 dBm          -17                                +33                                         45.2
-20.2              -24.8                              +25.2                                       45.4

We could use lower-Q resonator (insensitive to temperature?) and higher drive-level?  

2022-02-10

While testing PDH-lock, switched to Toptica Channel2 for EOM-source and PDH-mixer
EOM 25MHz -23.2 dBm, LO Phase 347.1 degrees, Input level 0 dBm

2022-02-09

Micromotion-scans from past days, voltage-vectors that change only one beam contrast, aka. columns of inv(Cfit)
(sign is arbitrary and depends on RF-phase vs. artiq-phase - should be constant as long as RF-siggen or artiq not booted?)

Voltage vector components (V12diff, V34cm, V34diff)

            VA                         VB                        VC
ID18981     ( 0.0091, 0.5237, 0.3895)  (2.5971, -1.6778, 1.2260) (2.0105, 0.5066, -3.2377)
ID18874     (-0.0041, 0.5938, 0.4672)  (3.3642, -1.9986, 1.5413) (2.5628, 0.5140, -3.9767)   (6x6x6 scan)
ID18865     (-0.0108, 0.5956, 0.4660)  (3.3781, -2.0160, 1.5509) (2.5882, 0.5313, -3.9668)   (6x6x6 scan)
ID18853     (-0.0121, 0.4117, 0.3734)  (2.4743, -1.5128, 1.0989) (1.9394, 0.3955, -3.1357)

sensitivity to uMotion seems to change slightly (scales all values?) so normalize to e.g. V34diff?

            VAn                  VBn                   VCn
ID18981     ( 0.0234, 1.3445, 1)  (2.1184, -1.3675, 1)  (-0.6210, -0.1565, 1)
ID18874     (-0.0088, 1.2710, 1)  (2.1827, -1.2967, 1)  (-0.6445, -0.1293, 1)
ID18865     (-0.0232, 1.2781, 1)  (2.1782, -1.2999, 1)  (-0.6525, -0.1339, 1)
ID18853     (-0.0324, 1.1026, 1)  (2.2516, -1.3766, 1)  (-0.6185, -0.1261, 1)
these agree slightly better between measurements?

Use average of these for alternative uMotion optimization search?
            VAn                  VBn                  VCn
mean        (-0.0102, 1.2491, 1) (2.1827, -1.3354, 1) (-0.6341, -0.1364, 1)
origininal un-normalized voltage vectors change one contrast by 100%, so use only <10% of these vectors at most for search?

Siglent settings
CH1 EOM-drive to Power Amplifier: 25 MHz, 45 mVpp, 0 deg phase
CH2 PDH-mixer: 25 MHz, 1.7 Vpp, 250 deg phase
PDH-mixer: no filter on LO/IF port, SHP-20 on photodiode signal to RF-port, IF to FALC inverting input

FALC-monitor 45.7 Hz peak

minus-k floating      -92 dBm
minus-k not float     -92 looks about the same...

2022-02-08