This page: http://monitor.mikes.fi/ionclock/

2019 archive

2019-12-20

08:00Z ion seems to have disappeared!?
Try a bit of 405, 1033, and 461..., and re-lock to Rb-line.

2019-12-19

10:00Z Longer run over lunch, 6x6x6 = 216 pts. n_phot=300k
11:30Z progress to pt 93/215 - so this run is >2 hours long..
Optimal voltages [ 0.24380421 26.67929547 43.62223335]
Data file 5009
Contrasts at Vopt ( 2.5, 2.7, 2.8) %

Ball-size is abs(contrast), +sign is green, -sign is red. sum figure shows sqrt(A^2+B^2+C^2)
optimal point is blue ball (size not to scale) in sum-figure.


0900Z: Run the NPLv3-umotion-optimizer, around previous voltages, with n_phot=100k
4x4x4 = 64 voltage-combinations, x3 beams. Data file 5004.
New optimal voltages (-5.5 V12cm): [ 0.24315127 26.67666472 43.61507129]
V1 = -5.7432, V2 = -5.2568, V3 = -16.938399999999998, V4 = 70.2918
Here n_phot=300k contrasts are: (2.5, 2.7, 3.1) % - (?not so great - same as before?)

micromotion contrasts are now slightly worse.
(A, B, C ) = (2.4, 3.1, 4.8) % repeated (2.0, 3.1, 4.6) % - measured with n_photons=300k and n_bins=25
voltages from y-day were (-5.5, +0.2668, +26.719, +43.503) V = (V12cm, V12dif, V34cm, V34dif)

Fluorescence from all beams ABC was quite steady at 37(1) kCPS through the night.
This is about 700 CPS in the usual 20ms detection window

2019-12-18

at some point Rb-lock was lost! detuning was down to 170MHz for tickler - this made the lock jump to the next Shiner-peak?
when locked to wrong shiner-peak, fluorescence was 200counts/20ms (required long camera exposure) - after re-locking to right peak >700counts/20ms.

micromotion investigations. How does V12cm change the optimal u-motion voltages?
d V12dif / d V12cm = -0.81 mV/V
d V34cm / d V12cm = 1.30 V/V - strong coupling!?
d V34dif / dV12cm = 18 mV/V

V12cm controls the secular ratio
V12cm = 0 V -> wz/wr = 1.52 and 1.57
V12cm = -3.5 V -> wz/wr = 1.76 and 1.84
V12cm = -5.5 V -> wz/wr = 1.93 and 2.02

secular frequencies with tickler
170MHz detuning seems to work (but see note on Rb-lock!), see rise in fluorescence at resonance
DDS attenuation 4dB for radial modes, 10 dB for z-mode
At -5.5 V12cm, RF 70mVpp, seculars (0.936125, 0.9805, 1.8918) MHz. Radial modes split by 44 kHz

video: https://www.youtube.com/watch?v=3vQdb2Ptwc8

overnight fluorescence monitor, gate time 1000ms, n_pts = 46800 (13 hours)
NOTE all beams ABC on!
data: 2019-12-18-counts.txt

2019-12-17

256x speedup stream: https://www.youtube.com/watch?v=bSQgo7BL8f4
slow stream: https://www.youtube.com/watch?v=Ey-IkPURY4o

overnight scans, variations in probe length and attenuation.
5kHz span, 10 Hz resolution, 499 pts/scan, ca 1 hour/scan
'center' scans, not randomized (seems to scan outwards from center?)
scan1: 20 dB, 5 ms
scan2: 20 dB, 10 ms
scan3: 20 dB, 20 ms
scan4: 20 dB, 40 ms
scan5: 22 dB, 10 ms
scan6: 22 dB, 20 ms
scan7: 22 dB, 40 ms
scan8: 22 dB, 80 ms
scan9: 18 dB, 10 ms
scan10: 18 dB, 20 ms
scan11: 18 dB, 40 ms
scan12: 18 dB, 80 ms
scan13: 18 dB, 5 ms


run5: same scan as run4, longer 20ms probe
run6: longer 40ms probe


run4: try to zoom in on left peak (-C1?)
center 75.9474 MHz, span 1 kHz, resolution 10 Hz, 101 points. Probe 10ms, attenuation 20 dB


run3: try I3=0mA, to separate Zeeman-components? Coil currents (-5, 0, 0) mA
center 75.9484 MHz, span 4 kHz, resolution 100 Hz, 41 points. DDS att 20 dB (from rabi-osc attempts 20 dB seems fine?)


run2: center 75.9484 MHz, narrower span 4 kHz, lower resolution 25 Hz, 161 points, DDS att 5 dB, 10ms probe, 20ms detection, 500/50 bright/dark.


run1: center 75.948 MHz, span 12 kHz, resolution 100Hz, 121 points. DDS att 5 dB. 10ms probe. 20ms detection 500/50 bright/dark.
ca 7s per 100 pulses
record-high 48% excitation!?
B-field seems low, peaks overlap


f_beat = 23.150
estimated f_corrected -330.396 MHz

Micromotion
NPL-optimization gives (0.2668, 26.719, 43.503) voltages. Here contrasts are (0.3, 0.5, 0.7)%. n_photons=300k

With no changes to bias-voltages, get contrasts of (5.5, 8.7, 13.3) %, detuning 210 MHz
The old voltages were (?) (0.246, 26.57, 44.2) V

2019-12-17 13:40Z Loading 1.60A, 6min 20s

setup changes: metglas 3rd layer. Toptica clock-laser (lock servo might not be optimal)

2019-12-10

Simulation: how many photons to collect into the correlation histogram?
<1% stdev in the S-contrast requires more than 2e4 photons.
ca 0.5% stdev in S expected with 1e5 photons.
<0.1% stdev requires >1e6 photons
Number of bins in the histogram is not important

2019-12-07

15:00Z: ion was dark from 23-local y-day evening. 405 or 422-re-lock doesn't help. shut down lasers.

2019-12-06 Independence Ion

Stream: https://www.youtube.com/watch?v=z9VFbs4FogY
128x speedup: https://www.youtube.com/watch?v=f3edhdwqXgc

scan1 Lorentzian fits to data, based on f_corr estimate -330.3895 MHz
lorentzian(x) = height*(width)/(pow(x - center,2) +pow(width,2))
Estimated AHM3 vs UTC is -2.5194e-12 or 1121 Hz @ SRS
Componentheightwidth / Hzcenter-SRS / Hz
-C42.1e-3241-9072
+C42.7e-3225+11291
C4 pair--+1110
-C21.5e-3182-2949
+C21.7e-3200+5179
C2 pair--+1115
-C12.3e-3203-937
+C11.9e-3203+3114
C1 pair--+1089

Estimate of B-field based on scan1 pairs is ~0.363(1) uT
Pairpeak-separation / HzZeeman shift / Hz/uTB = sep/(2*shift) / uT
C140515598.50.362
C28128111970.363
C42036327992.50.364

from livestream, ion lost 20:59:30Z. It was loaded 2019-12-04 13:37Z.

leave longer ca 1h scans running
center 75.9455, range 12 kHz, resolution 25 Hz, 481 points
probe 10ms, attenuation 20 dB
seem to detect C1 through C4 (not C5)
B ~0.36 uT with I = (-5, 0, -1) mA applied

data file e.g. "2019-12-06-scan1.txt"
scan1 (4794) through scan7 (4800) contain good data. scan8 (4801) has both a 5min dark period and the ion loss event.
scan9 through scan24 are invalid data

run5


12:15Z suddenly lost ion??... and then it returned at 12:20z after 5 min!?

run4
try I3 = 3 mA
-C1 at 75.9412
+C1 at ?
Run with a few different currents and plot in same figure
orange (0, 0, +3) run4: I3 = +3 mA
red (0, 0, +1) run4-1mA: I3 = +1 mA
pink (0, 0, -1) run4-minus1mA: I3 = -1 mA
blue (I1, I2, I3) = (+1, 0, -1) (did not move -C1 closer to line-center)
green (-1, 0 , -1) - now closer!
cyan (-2, 0, -1) - best so far
yellow (-3, 0, -1) - we now se also -C2 in the 3kHz scan? excitation-P for -C1 is lower? ex-P for -C2 is record-high!? run also the +side
tab:blue (-4, 0, -1)
tab:brown (-5, 0, 1)


run3
change I-driver state from "#" (edit mode?) to "^" (actual current-drive?) - maybe this will move C1?
same centers and ranges as before
+C1 at 75.94895 (moved only -100Hz?)
-C1 at 75.9415 (did not move much)


run2
search wider for C1
old (1mA) predicted center at 75.9416 (-C1) and 75.9486 (+C1)
observed at 75.94145 (25 jumps) and 75.94905 (26 jumps)
seems like the 2mA value is not in use? (repeat?)


run1, I3=2mA
center 75.9451 (no change)
range 7 kHz (should see C1 peaks, they were at +/-3.5 kHz previously)
step 100 Hz, 71 points


Increase I3=2mA - prediction is that this further decreases B.
interrupt run8 from y-day, it is taking too long...

2019-12-05

Clock transition run

run8
longer run, leave overnight
win-machine spontaneously rebooted in the evening (~21 local) !?! live-stream cut


4753 26dB attenuation rabi-flop
4752 rabi-flopping on -C2, DDS att 23 dB, range 1ms to 20ms

run7
zoom in on -C2 and get a linewidth (with first B-shield 2019-11-05 linewidth was ~800Hz )
Zeeman model predicts -C2 at AOM=75.9381 MHz


run6
peaks fit a B-field of 1.25 uT (but the prediction was 0.2uT from 1mA of current?)
try to get a wider view
back to calculated center (+2800Hz from run5)
wider range 30kHz, resolution 200Hz, probe 10ms, 151 points
Zeeman peaks offset +1.1 kHz from scan-center, with B=1.25 uT


run5
add 1mA of I3 coil current. ca 200uT/A -> B=0.2 uT
This should split C5 by 7.8kHz and C1 by 1.12kHz
larger range 10kHz but lower resolution 100Hz -> 101 points
20ms probe


run4
double range to 1kHz. 40ms probe, more attenuation 20 dB (seems OK from rabi-flopping)
10Hz resolution, 101 points


Now see high excitation probabilities, around 30% at best.
(4743) Rabi-flop, DDS_att = 5dB. Rises from 1ms to 4ms - then flat
(4744) Rabi-flop 10 dB att, rises until 8ms then flat
(4745) Rabi-flop 20 dB att, intially quadratic - good(!?) - from 0 to 6ms
(4746) Rabi-flop 30 dB att, narrower range 1ms to 30ms. too much attenuation - not much excitation.
(4747) 23 dB att.

run3
shift down center -2800 Hz
longer 40ms probe, 10 Hz resolution 1 kHz range
51 points


run2
longer probe 20ms, lower resolution 25Hz, larger range 2*6 kHz. 241 points. N_probe=100

run1
tau_probe=10ms, DDS_att=5dB, N_pulses=100, tau_det=20ms, N_bright=500, N_dark=50

6th run of NPL, over lunch, gave (0.258, 26.594, 43.829)
contrasts(300 kphotons, 35 bins) are (A, B, C) = (0.94%, 1.3%, 0.79%)
300 kphoton measurement takes (16, 23, 25) s to perform, depending on fluorescence amount from each beam

NPL-algorithm with 3 variables now seems to converge
detuning AOM 210MHz, V12cm = -5.5V (NOTE: this is FIXED in the v2 NPL-script!)
ABC-optimal point, 1st run: (0.250 , 26.573 , 43.814 ) (V12dif, V34cm, V34dif)
Here ABC-contrasts (2, 2, 2) %
60 k photons/histogram, 3 points scanned per voltage (27 points)

ABC-optimal point, 2nd run: small changes to optimum (-1 mV, +5 mV, +8 mV)
voltages = (0.249, 26.578, 43.822)
100 k photons/histogram, 5 points per voltage (125 points total)
here ABC-contrasts (2.5, 2.5, 2.5) % - not any better than previous optimum

2019-12-04


NPL-algorithm modified to only have 3 scanned parameters (V12dif, V34cm, V34dif)


Dashed lines show A-optimal and B-optimal voltages. Dash-dotted lines are shifted versions (2020-04) - probably not useful
pa = -1.5009 85.1762
pb = 1.6786 2.3214
For example a change of (V34cm, V34diff) = (+1, -1.5) should be along the A-optimal line.
These should be compared to the planes found in the 2019-12-19 data

AB-contrast optimal point found in (V34cm, V34dif) plane. C-contrast not optimal.
V-shaped bias-sweep plots, sine-shaped correlation histograms.

Micromotion minimization, need to move both ABC beams and ASE as bias-voltages change
Using V12cm = -5.5V to get axial/radial ~2

13:37Z Ion loaded 1.60A / 1.25 W and 6min 35s

2019-12-03

Filter-boards removed from clock-laser prestabilizer - now seems to stay locked for >8h.
Cavity drift from 8h of data: +18.093 mHz/s
OHDEV(drift-corrected) reaches 1e-15 at around 200s.
f_cavity = -490.2075 MHz (SRS) (morning 2019-12-03)

2012-12-02

Ion loaded 1456Z (1.60A and 8min 10s) - but lost 22:xxZ the same day

By scanning, found voltages that minimize A-contrast (but B/C beams do not cool in this state?)
Vbias = (-5.5, +1, 0, 80.4) V
A-contrast (repeats, n_photon = 60k or 80k): 0.9%, 0.45%, 1.2%, 0.58%
Clear minimum with pi-phase change at V34diff 80.4V. Sine-shaped correlation histogram

Secular frequencies: could not find radial splitting, see only one peak. why? (using A-beam)
70mVpp from agilent, and the usual 1.65Vpp monitor.
ARTIQ DDS as tickler, 4 dB attenuation for Radial, 10 dB attenuation for Axial.
Fluorescence dips or peaks, depending on cooling laser detuning.
Siglent siggen+bias-amp connected for DC-modulation (try this later also with shorting N-connector on helical-resonator!)
V12common / V Axial/Radial ratio Axial / MHz Radial / MHz
0 1.58 1.72 1.09
-2 1.72 1.7905 1.0387
-4 1.88 1.854 0.9846
-5 1.97 1.8848 0.9563
-6 2.06 1.9142 0.927

abs(qz)=0.32, trap voltage V0 = 390 V (assumes 0.75 trap efficiency)
az = 0 at V12common = -5.319 V

Loading at 1.70A gave two (or more?) ions

2019-11-29

Cavity modes
Estimated cavity mode spacing 501.305 MHz
Note that comb measures drift-corrected IR, not cavity frequency.
f_cavity - SRS / MHz sign, f_beat / MHz Wavemeter / nm Comb-line nr Cabity mode nr
-490.213 -23.145 1348.052 2 223 894 887 242
+11.092 +27.508 1348.051 2 223 896 887 243
+512.396 -21.840 1348.049 2 223 899 887 244
If cavity mode-numbers and abs-frequencies correct, mode spacing is 501 304 565 Hz
(measured against AHM3, with estimated frequency of -2.51e-12 wrt UTC(MIKE), maser is slow)

2019-11-28

Observed drift in 4h run: +24.733 mHz/s

Increase drift-correction by +4.49 mHz/s (single-pass), based on 4-hour run 2019-11-28 evening.

2019-11-25/26


ion lost 2019-11-26 at 17:24:52Z, storage time was ca 29 hours

Clock laser (briefly) locked to cavity
F_corrected = -330.386205 MHz
f_beat = 23.145390(50) MHz
With fixed 178.5 MHz AOM this gives line-center at AOM_Zeeman = 75.943103 MHz P_674_A-beam = 44 nW (5dB att. on Zeeman AOM)
20 ms detection window, bright=230, dark=30

Drift-correction was not updated recently, still runs with AOM-drifts of k0 + k1 = (6.532e-3 + 2.728e-3) Hz/s = 0.5 * 18.52 mHz/s

Try to optimize micromotion - but no clear minimum found
Longer NPL-algorithm run gives V12diff, V34common, V34diff = (+2.22, +23.138, +105.991)
This gives photon-correlation contrasts A/B/C = 18% 4% 14%
About 60 000 photons in one histogram seems necessary for good statistics

New RF-drive 16.716 MHz. 70mVpp gives 1.65 Vpp monitor as before.
2019-11-25 12:21Z Ion loaded with I_disp = 1.60 A after 4min 45s.

Bias-voltage source improved range to +/-168 V on V3 and V4

2019-11-14

Helical-resonator shield-adjustments.
After tuning impedance match (New RigExpert AA-55 Zoom)
- SWR 1.03 @ 16.7188 MHz
- Z=48.9 Ohm, R= 48.9, X= -0.96
- Q ~730...770

2019-11-08

pulse data from wide scan of 2019-11-05
30ms
26ms

Overnight results in Technicolor 3D:


(07:38) ion lost, tried 405nm but no change, checked 422nm Rb-lines - seems OK
from video, lost around 2019-11-07 21:39Z (was trapped at 2019-11-04 09:52Z)
camera intensifier battery-box needs a new 9V battery..

(07:33Z) clock-laser has unlocked at some point. when?

2019-11-07

Observed line is ca.800Hz (optical) wide - what B-field changes does this correspond to?
C2 sensitivity 11.190 kHz/uT, so 400Hz shift by 0.036 uT.
this is 2% of the assumed 1.56uT field at the ion
If we have a 36 nT peak AC-field (frequency?), can this be measured with a probe+meter?
How? Outside the shield, close to ion, and assume some AC attenuation?

(14:55Z) new center for scan: 75.93805 MHz
schedule overnight runs, 8pcs a 2hours = 16 hours.
all scans have same AOM range 1200Hz and AOM step 5Hz, 239 frequency-points per scan.
3rd run 50ms
50ms_run3
5th run 40ms
40ms_run5
1st run 30ms
30ms_run1
7th run 20ms
20ms_run7
2nd run 10ms
10ms_run2
4th run 5ms
5ms_run4
8th run 2.5ms
2.5ms_run8
6th run 1ms
1ms_run6

(14:40Z) New drift-compensation = [6.523 (old) + 2.728 (new) ]*2 = 18.52 mHz/s, from 58794.611

(13:17Z) combined plot, run1 and run2


(13:01Z) What effect does cavity-drift have? We currently compensate 2*6.532 mHz/s = 13 mHz/s
Measured overnight drift is 18.5 mHz/s
During 1h we have uncompensated drift of 3600s*5 mHz/s = 20 Hz
During 1 day, 470 Hz!

(11:54Z) start run2: same 60ms probe, range 1500Hz (down from 2kHz), AOM step 5 Hz (down from 10Hz). 200 shots/freq.
301 points, 25s/pt, expected duration 2h, will finish at ca.13:54Z
run2

re-lock clock laser
(values are 15 min averages, from Chronograf)
f_beat= 23.148089 (37) MHz (12:01Z)
f_cavity = -490.255964 MHz
f_corrected = -330.391669 MHz
cavity_drift = 0.024 Hz/s

Clock-laser unlocked during lunch-break scan...(11:21UTC)

Use only A beam, P_674 = 105 nW, try 200 pulses per frequency
Same -C2 center-frequency (75.9383 MHz), 2kHz range (down from 7kHz), 10 Hz resolution (down from 20Hz).
200 frequency points, 25-26s/point, duration 1.5 hours
run1 60ms: run1

overnight cavity frequency: 2019-11-07_fcavity.csv

2019-11-06

NOTE: all three beams ABC ON for cooling and probe
Scan area around -C2, with different probe pulse lengths= 30ms, 40ms, 50ms, 60ms, 70ms....
7200 Hz AOM scan range, 20Hz AOM resolution, 360 points per scan. (1 hour per scan?)
shorter detection window 10ms, collects ~350 photons in 10 ms.
-C2_fcenter = 75.9383 MHz
Fcavity = -490.257406 MHz
Fcorrected = -330.392137 MHz
f_beat = 23.148357 MHz
clock-cycle configuration (clearout, cool, detect, repum)=(10, 50, 10, 60)
bright=350, dark=25. threshold is geometric mean
run1 30ms: run1 (note randomized order of frequencies!)
run2 40ms: run2
run3 50ms: run3
run4 60ms: run4
run5 70ms: run5
run6 30ms: run6
run7 40ms: run7
run8 50ms: run8
run9 60ms: run9
run10 70ms: run10
run11 80ms: run11
run12 90ms: run12
run13 30ms: run13
run14 40ms: run14
run15 20ms: run15

all:

Clock laser unlocked at some point during morning? (was unlocked at 0740 UTC)
Some of the later data in the overnight run is bad.

2019-11-05

overnight runs

Overnight scheduled runs for 30, 26, 22, 18, 14, 9, 6, 3 ms probe pulses. Approx 10 nW in A-beam to ion.
Scan is 75.947MHz +/- 35 kHz (assumes B=50uT/b_att=1.56 uT is correct...?).
1000 points, approx 70 Hz AOM resolution, 140 Hz optical.

30ms lin scale


22ms lin sale


all scans, log scale:

Zeeman notes


Zeeman-split at 50uT is +/- 281, 560, 1121, 1400, 1961 kHz (for C1, C2, C3, C4, C5 components)
sensitivities 5.6124, 11.190, 22.415, 27.992, 39.217 kHz/uT (NRC email 26.5.2013)
Corresponding to gS=2.00248 gD=1.200486 and gS/gD = 1.66806
Barwood2012b reports gS/gD = 1.668057
Normalized by C1 sensitivity ratios are approx: (1, 2, 4, 5, 7) and differ from integers by about 0.02 at most.
Ratios for zeeman-split from above sensitivities are (1, 1.9938, 3.9938, 4.9875, 6.9876)

clocklaser notes

run1

try minimizing micromotion, without much success... need higher Vbias voltages?
lower 674 intensity 10-fold, to around 10nW at ion (28dB attenuation on 178.5MHz DDS AOM, ca 2uW at 674-launch).
use 3ms probe pulse
scan range around inner two Zeeman-components (from -C2 to +C2) from 2019-11-04.
1000 frequency points (ca 100Hz AOM-step), ca 2 hours.

Fit to data!?
center_freq = 75.947000 (+2 kHz SRS)
C5-shift = 0.030641
+C5 = 75.977641
-C5 = 75.916359
B_eff = 50uT/b_att = 1.56 uT

2019-11-04

2019-11-04 run2:
from 75.85 to 76.05 (200 kHz) in 5000 steps (~10 hours)
40 Hz AOM step, 80 Hz optical
try 16 ms probe pulse (?)

2019-11-04 run1: from 75.8465 to 76.0465 (200 kHz) in 1000 steps (~2 hours)
200Hz AOM step, 400 Hz optical step
first half of data is bad, ASE-overrides were ON...
8 ms probe pulse, maybe 100nW in A-beam.

2019-10-31 photo

Cooling laser detuning scan
Micromotion minimization with the Baynham-matrix was successful (?).
Measured contrasts before scans (A/B/C) = (1.0 % / 1.6 % / 5.3 %)
However only A and B beam scans were successful, data from C-beam looks strange?
Measured power (A/B/C) = (0.38 / 0.35 / 0.27) uW
Theory curve has detuning shifted by -1 MHz, background counts 1700 cps estimated, fluorescence collection efficiency 1/218

2019-10-30 photo

Canon EOS 60D, 5 s exposure, f/2.8 105mm Sigma Macro, ISO-3200. 13mm extension tube.

2019-07-12 Weekend

The 8ms results were interpreted as due to either 33uT or 66uT ambient B-field.


2019-07.13 ca 17:00+03 re-locked cooling laser - strange noise on Rb-signal!?
8ms pulses: sat-13-8ms.txt

Ion trapped on wednesday (after lunch?) was lost friday 19:50+03. 405nm did not help (H-Sr molecule??), A/B/C beams did not help.
Better diagnostics for cooling-laser needed - not sure if servo was at limit or not..
New ion trapped sat 2019-07-13 ca 10:30+03
New longer probe-time runs scheduled
2.0 ms, 4.0 ms, 8.0 ms

8000 frequency-points in 2 MHz span -> AOM step 250 Hz -> optical step 500 Hz.
100 pulses per frequency, ca 7 s per frequency or 16 hours per 8000 frequency-points.
674nm ca 100nW, 422nm ca 1.1 uW detuning_AOM=200MHz, beam A.
run1: probe 0.5 ms
run2: probe 1.0 ms
run3: probe 2.0 ms
run4: probe 4.0 ms

2019-07-12 Friday

1ms, lower power

Zeeman AOM att. 21 dB (was 15dB) - now approx 50 nW to ion

4ms

longer 4 ms pulse
A beam, ca 100 nW

2ms

longer 2ms pulse
A beam, ca 100 nW

2019-07-11 night

one beam, the A beam
cooling ca 1.5 uW
clock ca 100nW, 1ms pulses
detection window longer (was 20 ms), now 34 ms
AOM-scan-batch is 250 kHz / 1001 points. 8 batches = 8008 points in total

2019-07-11 day

2019-07-10 run

Optical frequencies denoted SRS are offsets from BIPM SRS value.
All three cooling beams, AOM = 200 MHz detuning.
All three clock beams, ca 100 nW in total, 1 ms pulse.
Estimate of drift-corrected cavity-light: -330.486522 MHz SRS.
AOM-shift from this is AOM_fixed +178.5 MHz + 2*AOM_Zeeman
So the high peaks are centered at +0.854 MHz SRS and split by +/-0.617 MHz
Jumps (more than 2/100):

2019-06-18

Ion photo
Canon 60D, Sigma f/2.8 105mm macro + XX mm extension tube, ISO-1000, 8 s exposure



Secular frequencies measured with tickler (on one outer electrode)
Here -6 VDC is applied to both outer electrodes in order to get an axial/radial ratio of ~2.005.
The common mode lowers the radial frequency and raises the axial frequency
Radial splitting ~43 kHz.

Without common-mode voltage on the outer electrodes the axial/radial ratio is ~1.54.
Radial splitting ~37 kHz.