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ID Date Author Type Categoryup Subject Text Attachments
  2245   Wed Aug 22 00:42:42 2018 awadeDailyProgressWOPONew PZT mounted mirrorKoji showed me the collection of PZTs at
the 40m.  I've epoxied a 9 mm mirror
to the end of a P-810.10 peizo
  2247   Thu Aug 23 12:49:17 2018 awadeDailyProgressWOPONew PZT mounted mirror mountedThe bake overnight settled at 64 C. 
This wasn't quiet the minimum recomended
for EPO-TEK 353ND but
  2255   Fri Oct 12 19:05:51 2018 awadeDailyProgressWOPOGluing 532 nm PZT mirrorI'm making a PZT mounted 532 nm mirror,
so I have some independant control of the
pumping light phase for optimizing the classical
  2257   Mon Oct 29 19:05:58 2018 awadeDailyProgressWOPOFixing MM into 532nm collimatorAfter a number of changes to the path for
the pump light (532 nm) it has be very difficult
to get any decent amount of pumping power
  2262   Wed Nov 28 12:14:35 2018 awadeDailyProgressWOPOMode field diameter choosing best patch for WOPO inputThere is some loss in fiber-to-fiber connection
when there is a different mode field diameter
between the two.  Ideally one would
  2268   Tue Dec 4 19:34:22 2018 awadeDailyProgressWOPODiabolo 532 nm power drop and retuningI restarted the Diabolo laser after
it had been shut down for a lab tour. 
The using the throlabs S130C head the 1064
  2273   Thu Dec 6 20:04:50 2018 awadeDailyProgressWOPODiabolo 532 nm power drop and retuningI've continued to have problems getting
the Diabolo laser SHG to lock. 

I get nice clean fundamental resonance
  2277   Fri Dec 7 20:31:06 2018 awadeDailyProgressWOPODiabolo: cleaning dust out of SHG unit, self heating issuesI've managed to vastly improve the
power output of the SHG by doing a little
cleaning inside the box.
  2280   Thu Dec 13 14:01:13 2018 awadeDailyProgressWOPODiabolo: contacted coherentI've contacted the people at Coherent
about getting instructions for repair or
whether they can still service this unit
  2281   Thu Dec 13 16:24:06 2018 awadeDailyProgressWOPODiabolo: baseline numbers for coherentSome numbers for the Diabolo laser for
reference (to quote to Coherent, if they
get back to us with help).
  2283   Wed Dec 19 16:48:18 2018 awadeDailyProgressWOPODiabolo: baseline numbers for coherentContact with Coherent re Diabolo

got in contact with Coherent they have provided
some instructions on aligning the laser cavity,
  2284   Thu Dec 20 19:20:50 2018 awadeDailyProgressWOPODiabolo: trialing SHG oven set temperature points to see if there is a maxima when lockedThe strategy locking at lower laser power
and optimizing phase matching temperature
by slowly walking the temperature and laser
  2286   Fri Dec 21 15:33:26 2018 KojiDailyProgressWOPODiabolo: trialing SHG oven set temperature points to see if there is a maxima when lockedThis means that you want to make the SHG
crystal longer. Is that true? If so, can
you change the temperature for the optimal
  2287   Fri Dec 21 15:51:27 2018 awadeDailyProgressWOPODiabolo: trialing SHG oven set temperature points to see if there is a maxima when lockedNo I don't think so.  The temperature
of the oven is important for the phase matching
condition.  Its the nob you can turn
  2289   Mon Dec 24 10:08:49 2018 awadeDailyProgressWOPODiabolo: back to power with deliberate pre-misalignmentI think I've managed to bring the power
of the Diabolo back to a usable level for
  2290   Mon Dec 24 12:07:18 2018 KojiDailyProgressWOPODiabolo: back to power with deliberate pre-misalignmentGreat recovery job!

  2291   Mon Dec 24 16:46:41 2018 awadeDailyProgressWOPOMM into 532 nm patch fiber (to be hooked up to WOPO)I had another look at MM the 532 nm light
into the P3-460B-FC-2 patch
cable.  After walking some lens positions
  2296   Wed Feb 20 10:38:46 2019 awadeDailyProgressWOPOFixing 532 nm polarization linearity issuesAlignment of the pumping 532 nm polarization
into the WOPO is important to getting the
correct phase matching condition.  For
  2297   Thu Feb 21 17:02:24 2019 awadeDailyProgressWOPOMixing down homodyne output from 1 MHzI want to get signal from about 1 MHz down
to around DC from my subtracted  homodyne
photodetectors. I'm planning to do something
  2298   Fri Feb 22 14:05:09 2019 awadeDailyProgressWOPOMixing down homodyne: 5th order elliptic filter (100 kHz)Making 5th order Elliptical Filter

couldn't find any filters that would
cut off above 100 kHz so I made my own using
  2300   Thu Feb 28 16:00:59 2019 awadeDailyProgressWOPOPol launch into PM fiberI've set up a rotating PBS and half-wave
plate to provide polarization adjustment
into the 532 nm fiber without misalignment
  2303   Tue Mar 12 16:35:43 2019 awadeDailyProgressWOPOPol launch into PM fiber 1064 nmI've replaced the SM fiber in the 1064
nm launch with a PM fiber (P3-1064PM-FC-5).
I also moved the fiber collimator (F240APC-1064)
  2304   Tue Mar 12 16:58:50 2019 awadeMiscWOPOTodo list W11These are things to get do this week on
WOPO experiment:

☑️ Reinstall 50:50
  2305   Wed Mar 13 12:44:41 2019 awade, anchalDailyProgressWOPOPol launch into PM fiber 1064 nm[awade, anchal ]

After a bit of reading I've
realized that the standard use of these PM
  2306   Wed Mar 13 17:49:14 2019 awadeSummaryWOPODamage threshold estimates for optical fibersThis is just a note about damage tolerances
for fibers so we have a reference of the
amount of power that can be used.  
  2316   Wed Mar 27 20:37:38 2019 awadeDailyProgressWOPOMeasuring TF Homodyne Photo Detector for WOPO experimentInitial measurment of PD TF

realize I never really measured the signal
transfer function for each of these Photo
  2318   Fri Mar 29 16:00:21 2019 awadeDailyProgressWOPORemeasuring TF Homodyne Photo Detector B after switching out foil capThis
set of measurments turned out to be bad.
  2324   Wed Apr 10 13:10:45 2019 awadeDailyProgressWOPORebuild of WOPO homodyne detectors using AD829[awade]

This post details the rebuild I
made of the transimpedance amplifiers (TIA)
  2327   Mon Apr 22 19:35:16 2019 anchal and awadeSummaryWOPOShot Noise Intercept Current measurement of PhotodiodesAndrew measured the output voltage noise
of photodiodes through an AC coupled pre-amplifier
(G=200, 0.7 nV/rtHz) while varying the
  2331   Tue Apr 30 19:52:14 2019 awadeHowtoWOPOConfiguring Zurich box serverAs I couldn't find this on the 40m
elog/wiki I'm putting notes here on how
to configure a fresh webserver + python server
  2332   Wed May 1 14:34:53 2019 awadeDailyProgressWOPOOutput chain and demodulation of squeezing signalThe detectors have been verified to have
a low intercept current, that will give us
good clearance of our shot noise to dark
  2345   Thu May 16 16:52:46 2019 awadeHowtoWOPOZurich box python accessThe Zurich box can also be accessed via
a python API.  Its a little bit opaque
in some points on how this works as their
  2349   Wed May 22 15:07:09 2019 awadeDailyProgressWOPODemodulation and subtraction for homodyne detector with Zurich boxFor the detection of squeezed light the
homodyne detector  is now configured
for digital subtraction in post processing.
  2352   Thu May 23 15:29:58 2019 awadeDailyProgressWOPOMaking time domain measurement of noise power in homoydne with WOPO pump onIn order to see squeezing I want to scan
the phase of the homodyne relative to the
squeezed light and see the variations in
  2354   Sun May 26 21:24:38 2019 awadeDailyProgressWOPOExcess noise when pumping: checklist for Monday.There are a few other possibilities
for the excess noise when injecting pump,
this is a checklist for me to run through
  2356   Wed May 29 15:24:33 2019 awadeDailyProgressWOPOUpdate to checklistI had a look at a few of these things. 
I've found that it doesn't seem to
be caused by heating of the beam splitter,
  2723   Tue Feb 22 07:53:06 2022 YehonathanUpdateWOPOWaking up WOPO{Shruti, Yehonathan}

On Friday, we came down to QIL
to poke around the WOPO setup. The first
  2725   Fri Feb 25 17:09:53 2022 shrutiUpdateWOPOWaking up WOPO - green beam[shruti, yehonathan]

SHG and 532 nm beam alignment

brought over 532nm/1064nm laser goggles from
  2727   Wed Mar 2 14:38:55 2022 YehonathanUpdateWOPOWaking up WOPO - some more fiddling and a plan{Shruti, Yehonathan}

We made some a list of some random
questions and plans for the future. We then
  2728   Fri Mar 4 11:49:45 2022 shrutiUpdateWOPOWaking up WOPO - attempts at readout[Yehonathan, Shruti]

1. Doubling cavity and green beam

we had left the lasers ON with the shutters
  2731   Thu Mar 10 17:12:01 2022 awadeUpdateWOPOWaking up WOPO - attempts at readout[awade]

Good to see this experiment being
  2733   Wed Mar 16 12:22:44 2022 YehonathanUpdateWOPOWaking up WOPO - attempts at readout{Shruti, Yehonathan}

Yesterday, we measured a bunch
of noises.
  2735   Tue Mar 22 09:19:38 2022 shrutiUpdateWOPOWaking up WOPO - back to green path[Yehonathan, Shruti]

Yesterday we went back to fiddling
with the green path. Soon after opening the
  2759   Wed Apr 20 00:12:12 2022 YehonathanUpdateWOPOStill figuring out the readout electronics and fixing of some stuff{Yehonathan, Shruti}

1. Grabbed 30Hz-3GHz HP spectrum
analyzer from the Cryolab. Installed it in
  2760   Thu Apr 21 10:33:33 2022 shrutiUpdateWOPOStill figuring out the readout electronics and fixing of some stuff[Yehonathan, Shruti]


First we turned on the relevant
  2762   Mon Apr 25 11:08:35 2022 YehonathanUpdateWOPOStill figuring out the readout electronics and fixing of some stuff{Shruti, Yehonathan}

We realized that the PD amp circuit
only requires a 5V DC supply so we try that.
  2764   Thu Apr 28 14:12:20 2022 YehonathanUpdateWOPOStill figuring out the readout electronics and fixing of some stuff{Shruti, Yehonathan}

We went to the e-shop to investigate
the PD circuits. Completely confused about
  2777   Thu Jun 2 10:28:26 2022 YehonathanUpdateWOPOInstalling 1811 PDs[Shruti, Yehonathan]

We took newport 1811
PDs, one from CTN lab (suspicious) and one
  2796   Wed Jul 20 15:55:41 2022 YehonathanUpdateWOPOInstalling 1811 PDs{Yehonathan, Paco}

We comfirmed that the DC ouput
of one of the 1811s is bad. We set out to
  2800   Tue Aug 23 22:23:06 2022 awadeUpdateWOPOInstalling 1811 PDsI recall at one point we had one of these
NF1811 with a broken power suply pin.  It
was from a limited production run with the
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