40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  Coating Ring-down Measurement Lab elog, Page 3 of 18  Not logged in ELOG logo
New entries since:Wed Dec 31 16:00:00 1969
ID Date Author Type Category Subjectup Text Attachments
  289   Wed Feb 1 16:58:10 2017 GabrieleGeneralCharacterizationExcitation testsThe excitation is working fine. However,
there is a large cross coupling in the excitation
between channels: so if I switch on only
  
  422   Thu Aug 24 07:40:33 2017 GabrieleGeneralMeasurementsExcitations with new ESD2017-08-23


Excitations


Quiet
time before excitation: 1187577794
Excitation broadband: 1187577826
  
  424   Fri Aug 25 07:25:32 2017 GabrieleGeneralMeasurementsExcitations with new ESDThe results show very low Q values, so
we suspected some issues. Yesterday we openend
the chamber and moved the ESD up, as high
  
  425   Fri Aug 25 19:29:07 2017 GabrieleGeneralMeasurementsExcitations with new ESDNew set of excitations after raising the
ESD:


Quiet time before excitation:
 results_2017_08_25d_CR0.png 
  105   Thu Sep 1 02:13:33 2016 GabrieleOpticsCharacterizationExpected frequencies for the 75 mm disks with flatsHere are the nominal parameters of the
disk with flats

 allmodes_aggregated.pdf 
  213   Mon Nov 28 16:02:16 2016 GabrieleGeneralGeneralExpected frequencies for the MIT samples


  
  26   Wed Jun 29 16:44:17 2016 GabrieleGeneralConfigurationFirst disk eigenfrequencyThe following table shows the lowest eigenfrequency
(Hz) for different sizes of disks

 disk_75mm_1mm.pngeigenfrequencies.png 
  107   Mon Sep 12 16:00:06 2016 GabrieleGeneralDaily ProgressFirst fully automated measurements of ring downI finished the first version of the automation
software to measure the ring down of the
disk modes. I tested it with the new substrate
 step_1.pngstep_2.pngmain.pngScreenshot-Ringdown-1.png 
  49   Mon Jul 18 17:46:04 2016 GabrieleGeneralDaily ProgressFirst look at QPD signalsHere's the first spectrum of the QPD
X and Y signals, acquired with the digital
system. Roughing and turbo pumps are still
 Screenshot.png 
  93   Sat Aug 20 22:18:26 2016 GabrieleGeneralDaily ProgressFirst measured QsUsing the first ring down of the day (GPS 1155754513
+ 3600 seconds), I computed the amplitude
of each of the modes already identified,
 22x 
  53   Tue Jul 19 17:21:48 2016 GabrieleGeneralDaily ProgressFirst modes excited!We can't generate any arbitary signal
with the real time model, since awg is not
working properly yet. For the moment being
 excited_modes.png 
  285   Tue Jan 31 16:50:55 2017 Gabriele, AlenaGeneralVacuumFirst pump-down with setupThis afternoon we started the pump-down
with all the system installed into the chamber.
Unfortunately the IGM vacuum gauge isn't
  
  92   Sat Aug 20 17:01:10 2016 GabrieleGeneralDaily ProgressFirst ring down measurementsEverything is working pretty well. This
morning the pressure was about 1.2e-6 Torr.
I connected the high voltage amplifier and
 modes.pdf 
  292   Mon Feb 6 14:09:07 2017 GabrieleGeneralMeasurementsFirst set of parallel measurements completedThe new laser is still acting up a bit,
with a wandering line moving sometimes inside
the band. Nevertheless, I could perform the
 results_06-Feb-2017.pngresults_2017_02_06a_CR1.pngresults_2017_02_06a_CR2.pngresults_2017_02_06a_CR3.pngresults_2017_02_06a_CR4.png 
  267   Thu Jan 19 14:27:02 2017 AlenaGeneralVacuumFirst vacuum test new chamberTurbo pump controller (new chamber) was
configured. Need to reduce the frequency
or setup a standby mode. First pump down:
 20170119.png 
  82   Sat Aug 13 14:05:02 2016 GabrieleGeneralDaily ProgressFirst work on the measurement user interfaceToday I started programming part of the
user interface that will be used to perform
the measurements. Not much implemented so
 Screenshot-C.Ri.Me..pngcrime.png 
  87   Tue Aug 16 11:57:03 2016 GabrieleElectronicsConfigurationFixed cymac3 network and time issueThe cymac3 internal clock was off by about
10 seconds. When I tried to start the NTP
service, I found out that the cymac3 couldn't
  
  364   Wed Jul 5 16:40:51 2017 ZachElectronicsModelingForce disparity-improvement2017-07-05


In order
to improve my data I shrunk the region of
the finer meshing slightly and made the mesh
 1ForceE2.png1ForcePE.png 
  363   Wed Jul 5 12:01:51 2017 ZachElectronicsModelingForce plots-Correct plots, force issue2017-07-05


I sorted
out my mathematical lapse in logic and computed
the correct force profiles in the perpendicular
 Force_E2.pngForce_PE.png 
  368   Fri Jul 14 16:43:24 2017 ZachElectronicsModelingForce profile matlab script2017-07-14


I have completed
a rough, but functioning script that calculates
the modal force profiles. The force values
 forces.mfaster.m 
  278   Thu Jan 26 17:06:59 2017 GabrieleGeneralDaily ProgressFour fold measurement system installationToday I installed the four GeNS systems
into the chamber, connected the ESD to the
HV feedthrough and put the periscopes in
 2017-01-26_14.03.46.jpg2017-01-26_14.03.57.jpg2017-01-26_14.04.06.jpg2017-01-26_14.04.06.jpg2017-01-26_15.45.44.jpg 
  282   Mon Jan 30 15:16:54 2017 GabrieleGeneralDaily ProgressFour samples in chamber
checked that the high voltage paths
are working:

the DAC signal
is properly received and amplified by the
 Screenshot-Untitled_Window-1.png2017-01-30_15.28.02.jpg2017-01-30_15.10.40.jpg2017-01-30_15.27.57.jpg2017-01-30_15.10.48.jpg 
  356   Tue Jun 27 14:17:47 2017 ZachElectronicsModelingFurther plots and improving models2017-06-27


I built
a new model of the ESD to determine whether
or not the spikes in the electric field at
 E_field_corner.pngE_field_round.png 
  476   Mon Mar 5 11:03:18 2018 Gabriele, AnthonyGeneralMeasurementsFused silica substrated for metallic glass tests2018-03-05


10:45am
in chamber:

AK_01 in CR1
AK_02
in CR2
AK_03 in CR3
AK_04
  
  873   Tue Jun 9 11:04:28 2020 GabrieleGeneralMeasurementsGaAs S16008052020-06-09


11:00 am
in chamber

GaAs in CR1
S1600805
in CR2


11:04 am
  
  402   Thu Aug 10 10:47:54 2017 ZachElectronicsModelingGeometry Ratios2017-08-10


The attached
plots compare the new and old geometries
with .5 mm and 1 mm sample gaps. They are
 Optimization_plot_lin.pdfOptimization_plot_log.pdf 
  56   Thu Jul 21 12:10:14 2016 GabrieleGeneralDaily ProgressGlitch huntingYesterday I could clearly see the glitches
as jumps in the time domain plot of X and
Y signals, and trace them to somewhat harder
 2016-07-21_10.12.50.jpg2016-07-21_09.45.29.jpg2016-07-21_10.01.13.jpg 
  54   Tue Jul 19 20:19:38 2016 GabrieleElectronicsConfigurationGlitches are a digital artifactThe glitches I saw in the data happens
roughly every second, even though not
exactly on the second. They are suddend jumps
 glitches.pngglitches.pngjump1.pngjump2.png 
  57   Thu Jul 21 14:58:26 2016 GabrieleElectronicsGeneralGlitches are of digital originSo here's the final proof that the
glitches I see are digital:


There is a positive jump
 glitches_hene_table.pngglitch_hene_table_2.png 
  61   Mon Jul 25 17:44:13 2016 GabrieleElectronicsCharacterizationHigh frequency noise budgetI measured the noise sources limiting the
QPD sensitivity. Unfortunately, I had to
do some MATLAB tricks to get rid of the glitches:
 qpd_noises.pngqpd_noise_budget.png 
  62   Tue Jul 26 11:45:03 2016 GabrieleElectronicsCharacterizationHigh frequency noise budgetJust to confirm that my noise estimates
make sense, here's a plot of the not-normalized
QPD signal that gives the X motion (sum and
 noise_budget.pngnoise_budget.pngnoise_budget_whitened.png 
  226   Mon Dec 5 16:35:05 2016 GabrieleElectronicsGeneralHigh voltage relaisWe want to be able to drive any combination
of the four samples in the new setup, by
using only one HV amplifier.
 2016-12-05_16.06.51.jpg2016-12-05_16.18.56.jpg2016-12-05_16.18.49.jpg 
  276   Wed Jan 25 10:02:23 2017 GabrieleElectronicsDaily ProgressHigh voltage system in placeThis morning I installed in the clean room
the high voltage amplifier and the high voltage
relays. Everything is cabled as planned.
  
  22   Fri Jun 10 13:44:06 2016 GabrieleElectronicsConfigurationHow to setup a workstationInstructions on how to setup a workstation
are available here:

https://nodus.ligo.caltech.edu:8081/Cryo_Lab/1135
  
  148   Tue Oct 25 11:10:37 2016 GabrieleGeneralMeasurementsImage of S1600433This is an image of the sample S1600433
under the microscope, courtesy of GariLynn:

Link
 IMG_3150.JPG 
  386   Tue Aug 1 16:10:42 2017 ZachElectronicsModelingImproved Gap Sweep2017-08-01


I completed
an improved sweep of the gap between the
ESD arms. I resolved some code issues, since
 Better.jpgmode_14.jpgmode_19.jpgmode_25.jpg 
  286   Tue Jan 31 16:55:17 2017 GabrieleGeneralDaily ProgressImproved autocenter, excitation not working, wandering line The autocenter script wasn't working
in a very robust way (sometimes the socket
connection to the controller failed, some
 wandering_line.pngwandering_line.png 
  116   Tue Sep 20 15:34:00 2016 GabrieleOpticsDaily ProgressImproved optical lever layoutGoal

Improve the optical setup,
by increasing the response of the QPD to
disk motion.
 beam_profile.png2016-09-19_11.33.48.jpg2016-09-20_15.50.21.jpglayoutpng.png 
  270   Fri Jan 20 17:20:20 2017 GabrieleOpticsDaily ProgressInput part of the optical lever setup installed and alignedToday I installed and aligned part of the
optical components for the optical lever
of the new setup. For the moment being I
 optical_setup.png 
  272   Mon Jan 23 16:29:52 2017 GabrieleOpticsDaily ProgressInput part of the optical lever setup installed and alignedToday I cabled and installed the four QPD,
in a temporary position. I also assembled
four picomotor mounts that will be used for
  
  421   Wed Aug 23 14:11:13 2017 Zach, GabrieleElectronicsMeasurementsInstalling ESD Prototype2017-08-23


Installed
ESD Prototype design by taping it to the
older design, we then lowered the mount until
 image1.JPGimage2.JPG 
  58   Fri Jul 22 14:22:10 2016 GabrieleElectronicsConfigurationInvestigations on the signal jumps[Rolf, Ben, Rich, Gabriele]

Rolf couldn't find any good
explanation on the software side for the
 glithces.pngglitch2.png 
  450   Thu Jan 11 15:40:28 2018 GabrieleGeneralMeasurementsLMA sample (post annealing)2018-01-11


3:35pm in
chamber CR1
3:36pm roughing pump
on
3:46pm turbo pump on
Excitations

Quiet
  
  432   Thu Oct 5 14:28:35 2017 GabrieleGeneralMeasurementsLMA substrate2017-10-05


2:17pm in
chamber

LMA substrate after
cleaning in CR1


2:20pm
  
  358   Thu Jun 29 13:15:01 2017 Alastair, GabrieleGeneralGeneralLaser polishingWe laser polished S1600546, 547, 548, 549,
550 and 551
  
  542   Fri Jun 22 10:53:06 2018 AlenaGeneralGeneralLaser failureOne of the HeNe lasers died (the one for
measuring slots CR2 and CR4). It had no outgoing
light when I came in this morning. I connected
 20180622_112134.jpg20180622_112138.jpg 
  220   Thu Dec 1 11:59:21 2016 Gabriele, AlastairGeneralGeneralLaser polishing Today we laser polished S1600484, S1600485
and S1600486.

 2016-12-01_11.26.30.jpg2016-12-01_11.15.39.jpg2016-12-01_11.34.32.jpg2016-12-01_11.26.41.jpg 
  205   Mon Nov 21 16:21:12 2016 Gabriele, AlastairGeneralGeneralLaser polishing of S1600487The sample has been laser polished this
afternoon, 0.5mm/s, average power 23 W.

We moved the lens that focuses the
  
  208   Tue Nov 22 14:11:38 2016 GabrieleGeneralMeasurementsLaser polishing of bad disk improves Q, but they're still not very goodLaser polishing of a sample from the second
batch (S1600487, bad Q as out of the box)
improves the Q values, but they're still
 polishing_Qs.pngpolishing_Qs.png 
  101   Mon Aug 22 16:59:13 2016 Gabriele, AlastairOpticsDaily ProgressLaser polishing of the disk edgesWe set up a test facility for laser polishing
the disk edges, using the CO2 laser in the
TCS laboratory. We focused the beam with
 2016-08-22_14.47.47.jpg2016-08-22_13.52.02.jpg 
ELOG V3.1.3-