40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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ID Dateup Author Type Category Subject Text Attachments
  1851   Tue Oct 20 20:41:59 2020 KojiSummaryGeneralDelivered the instrument / components for 2um ECDLI brought in the instrument and components
for 2um ECDL:

1. SAF Gain chip / SAF1900S / Qty2
  1852   Wed Oct 28 17:29:14 2020 PacoSummaryGeneralLab organizationI entered Crackle lab circa ~11:15. I started
some basic lab inventory and started cleaning/organizing
stuff. We will use the first optical table
  1853   Mon Nov 2 18:23:46 2020 PacoDailyProgressGeneral Today; entered lab at ~09:08. I verified
the orientations of the aspheric lenses and
blaze gratings relative to the flextures,
  1854   Wed Nov 4 01:25:37 2020 KojiSummaryOpticsAspheric Lenses and Grating Plates bonded on their mountsAttachment 1: Black Diamond
(GeSbSe) Lens was mounted on the flexure
mount. The flat surface should face to the
  1855   Fri Nov 6 10:47:49 2020 PacoDailyProgressGeneralConnecting SAF1900SHere is a summary for how to connect the
SAF1900S gain chip to TED200C temperature
controller and LDC220C diode current driver.
  1856   Fri Nov 6 11:58:02 2020 KojiLab InfrastructureGeneralECDL Gratings / Lenses delivered. Powermeter lending from OMC LabThe gratings and aspheric lenses glued
on the mounts were delivered to the lab on
  1857   Mon Nov 9 17:38:18 2020 PacoDailyProgressGeneralSAF gain chip first lightEntered Crackle ~ 8:47 AM.

Briefly fixed the LDC220C connection
to the SAF1900 as described previously,
  1858   Tue Nov 10 00:02:20 2020 KojiDailyProgressGeneralSAF gain chip first lightVery exciting to see the gain chip curve!

Grating orientation: Whaaat...
If you already have the 1um laser SOP approved,
  1859   Tue Nov 10 10:32:57 2020 PacoDailyProgressGeneralSAF gain chip first lightSet grating in front of 1064 nm beam (current
set to 1.058 A for a beam visible on the
IR card). After testing both orientations,
  1860   Wed Nov 11 12:28:33 2020 PacoDailyProgressGeneralEP30 softeningAttempted two methods to soften EP30-2,
the results are summarized below.

(a) Heat -- Used the heat gun set
  1861   Wed Nov 11 12:55:18 2020 PacoLab InfrastructureGeneral1064 pump power curveLog of the output power vs current in the
1064 nm (Innolight) pump laser. The crystal
temperature was set to 45.5 C, and the current
  1862   Wed Nov 18 09:14:11 2020 shrutiMiscEquipmentLoanbeam profilerI placed the two beam profilers with the
two laptops and chargers right inside the
Crackle lab, as requested by Paco.
  1863   Wed Nov 18 14:29:00 2020 KojiMiscEquipmentLoanbeam profilerNote: Please don't try to connect these
old Windows to the network. We just extract
the data via USB etc, and that's all
  1864   Wed Nov 18 17:49:05 2020 PacoDailyProgressOpticsbeam profilesUsed BeamR and WinCamD to profile the two
light sources (ECDL and OPO pump) 

(1) ECDL; profile 19** nm beam
  1865   Fri Nov 20 18:43:31 2020 KojiSummaryGeneralDelivered the instrument / components for 2um ECDL> Temp Controller / TED200C
/ Qty 2 Note One unit temporary used by 2um
PD test setup
  1866   Mon Nov 23 11:43:26 2020 PacoMiscEquipmentLoanbeam profilerShruti took back the beam profilers today
AM to Cryo.

  1867   Mon Nov 23 11:44:13 2020 PacoMiscGeneralMDT694B python controllerToday entered lab ~ 09:00. Over the weekend
I coded a PySerial wrapper for the thorlabs
MDT694B single channel piezo controller.
  1868   Tue Nov 24 12:32:56 2020 KojiMiscGeneralMDT694B python controllerWow!
This is really cool! I didn't
realize that this small box has such many
  1869   Tue Nov 24 16:30:59 2020 PacoMiscEquipmentLoanbroadband EOMBorrowed 1 (new focus) broadband EOM from
for temporary use in Crackle (2 um OPO exp)
  1870   Tue Dec 1 18:37:09 2020 PacoDailyProgressOpticsOPO pump steeringEnter lab ~09:20. Today I spent a while
looking at the broadband EOM drivers used
in CTN (presently optimized for 37 MHz) and
  1871   Thu Dec 3 12:20:19 2020 AnchalSummaryElectronicsTuned and characterized EOM Driver for 37 MHz phase modulationMeasurement details:

New Focus 4004 broadband IR phase modulator
to the output of the SN06 EOM driver.
  1872   Wed Dec 9 17:47:12 2020 PacoMiscElectronicsquick test of 14.75 MHz RFPDOn Monday, tested a 1998 (Rev. 0) RFPD
originally found in Crackle (serial #010).
Looks like it was first resonant at 24.493
  1873   Wed Dec 9 18:03:31 2020 PacoDailyProgressGeneralLab organizationIn the process of adding a PC/controls,
and other related instruments, reorganized
items in the lab. Threw out some boxes and
  1874   Fri Dec 11 16:04:36 2020 PacoLab InfrastructureOpticsPPKTP crystalsTwo crystals from Raicol arrived. Picked
them up from Downs today and inspected them
(see photos below). The lengths are nominal
  1875   Fri Dec 11 17:53:07 2020 PacoDailyProgressElectronicsUPDH box alternative power supplyToday, after struggling to find a 4-pin
circular power supply cable for the UPDH
box (still interested btw) punched a hole
  1876   Tue Dec 15 13:00:41 2020 anchalLab InfrastructureEquipmentLoanReceived Marconi and Rb clock from CTNReceived one Marconi 2023A (#539) from
CTN and an SRS FS725 Rb clock. (See CTN/2605)
  1877   Wed Dec 16 22:13:43 2020 anchalMiscEquipmentLoanTook delay line box, compressed nitrogen cylinder and lens
Took a delay line box DB64 from
QIL from the WOPO table. The box was marked
Crackle on it.
Took the compressed
  1878   Wed Dec 16 22:38:55 2020 KojiMiscEquipmentLoanTook delay line box, compressed nitrogen cylinder and lensPhotos, please, because we don't allow
a free-rolling cylinder in a lab.
  1879   Thu Dec 17 11:59:14 2020 PacoMiscEquipmentLoanbeam profilerBorrow both beam profilers and laptops
from WB 264A.
  1880   Thu Dec 17 12:01:54 2020 PacoLab InfrastructureOpticscrystal ovens, clips and controllersCovesion order arrived, containing 2x

Crystal oven (20 mm long)
Clips (for mounting crystals)
  1881   Mon Dec 21 16:35:14 2020 AnchalDailyProgressOpticsTook beam profile of laser right off the head
This is a repetition
of SUS/1864.
  1882   Tue Dec 22 15:54:03 2020 AnchalDailyProgressOpticsTook beam profile of near EOM area
After installing a 400mm focal
length plano-convex lens at 24" from
the laser head at (20, 12), we found that
  1883   Wed Dec 23 15:43:01 2020 PacoDailyProgress OPO cavity assemblyLaseroptik optics (4x pairs of cavity mirrors)
arrived earlier this week, so I began assembling
the input mirror with Noliac (NAC2124) PZT.
  1884   Mon Dec 28 15:51:51 2020 AnchalDailyProgressOpticsMode matching solution for CavityGoals and restrictions:

Use the fewest lenses as
The beam widths in both
  1885   Wed Dec 30 09:57:56 2020 PacoDailyProgressOpticsDOPO crystal ovenAssembled first DOPO oven with the crystal.
The components (shown below) are:

Oven clip
  1886   Thu Dec 31 16:41:59 2020 AnchalDailyProgressOpticsMode matching solution for CavityGoals and restrictions:

the fewest lenses as possible.
beam widths in both onward and reflection
  1887   Wed Jan 6 09:34:34 2021 AnchalDailyProgressOpticsCorrected analysis and found better solutions.Errors in the previous analysis

we wrongly assumed. that the reflected light
from the cavity would be as if a reflection
  1888   Thu Jan 7 09:44:52 2021 PacoDailyProgressOpticsShaping the OPO cavity modeSummary of solution number 2 (from previous

After installing the lenses, mirrors
  1889   Thu Jan 7 17:09:16 2021 Paco & AnchalDailyProgressOpticsMode matching OPOFresh attempt at mode matching. For this,

Installed the oven, plugged
it to the controller and went to the nominal
  1890   Fri Jan 8 17:00:26 2021 AnchalDailyProgressOpticsIncluded lens made by cavity input mirror and distrotion due to crystal

  1891   Fri Jan 8 17:17:19 2021 AnchalDailyProgressOpticsIncluded lens made by cavity input mirror and distrotion due to crystalError in previous calculations:

We did not take into account
the effect of cavity input mirror on the
  1892   Wed Jan 13 17:52:35 2021 PacoDailyProgressOpticsOPO cavity resonanceObserved first resonant transmitted (&
reflected) light from the DOPO cavity; the
PZT scan was centered at 31 V, at 2 Hz, with
  1893   Fri Jan 15 10:57:39 2021 PacoLab InfrastructureEquipmentLoanBorrow AG4395A and EOM Driver TF re-tuneSee equipment borrowing note here.

Attempting TF measurement for resonant
EOM driver, but not having luck reproducing
  1894   Fri Jan 15 17:21:53 2021 PacoDailyProgressElectronicsRFPD TFRecord TF for RFPD SN09, resonant at 36
MHz, using the exact procedure as with EOM
Resonant Driver.
  1895   Tue Jan 26 11:33:32 2021 ranaDailyProgressOpticsIncluded lens made by cavity input mirror and distrotion due to crystal

  1896   Tue Jan 26 11:34:51 2021 ranaDailyProgressOpticsIncluded lens made by cavity input mirror and distrotion due to crystalwould be good if you could find a solution
that is not very sensitive to precise lens
  1897   Tue Jan 26 11:47:12 2021 PacoDailyProgressGenerallow quality PDH error signalAfter getting what looked like a decent
cavity reflection signal, installed RFPD
yesterday. For this, removed the lens that
  1898   Tue Feb 2 10:32:25 2021 AnchalSummaryOpticsFiguring out how much astigmatism is hurting usMethods

the actual measured beam profile in X and
Y directions.
Propagate them with
  1899   Tue Feb 2 17:39:52 2021 PacoDailyProgressOpticsre: Figuring out how much astigmatism is hurting usMotivated in part by the conclusions below,
improved estimated mode matching efficiency
from a poor 13% at the beginning of day to
  1900   Thu Feb 4 16:46:06 2021 PacoDailyProgressOpticsOPO cavity lockDemodulation stage

Update on
demod. for OPO cavity lock. Last
related elog entry described prevalence
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