Phase noise measurement of the Amplitude MIKAN, posted by Ronic Chiche at Optical room about lasers and optics | detectors and electronics
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Installation of the MIKAN.
powermeter (with OD1) just after the oscillator shows 440mW for 4A of the MIKAN pump current.
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Phase noise measurement of the Amplitude MIKAN, posted by Ronic Chiche at Optical room about lasers and optics | detectors and electronics
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Coupling into a 50-50% fiber coupler using the Thorlabs XYZ table NanoMax TS.
We reached 117mW after the 50% arm which means we coupled about 230mW (the coupling better than 50%).
Ronic |
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Theoretical Finesse, Gain and Coupling, posted by Ronic Chiche at Optical room about lasers and optics
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For spherical mirrors M3 and M4 (batch C117I054) the reflectance (R) is around 99.9987% (if T+R=1 => T=13ppm)
For plan mirror M2 (batch C217G054) the reflectance (R) is around 99.9977% (if T+R=1 => T=23ppm)
(1) => For plan mirror M1 (batch C217H023) the reflectance (R) is around 98.96% and transmittance (T) is around 1.14% (T=11400 ppm) |
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Locking with fast analog loop on AOM, posted by Ronic Chiche at Optical room about lasers and optics
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in addition to the standard locking scheme with the GHz laser PZT,
we added an AOM after the PDH modulation EOM and we drove it with an FM modulated signal generator (FMDev = 2.4MHz) seeded by the error signal.
(we didn't put a 50ohm plug to adapt the error signal coming from the PDH box, otherwise, it is too much smaller) |
PZT resonant frequencies, posted by Ronic Chiche at Optical room about mechanics | lasers and optics | detectors and electronics 
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we have excited the PZT with a swept sinus wave from 1kHz to 10kHz and from 10kHz to 100kHz.
here are the 2 different spectrums:
- the 1kHz-10kHz is a standard spectrum where we see the impedance behavior of the PZT: Zpzt ~ 1/jCw |
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Amplitude GHz oscillator phase noise with PZT effect, posted by Ronic Chiche at Optical room about lasers and optics
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3 phase noise measurements made on the Amplitude GHz oscillator with different PZT configurations :
- black curve: PZT connector is open
- green curve: PZT connector is shorted by 50 ohms |
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Phase noise measurement of the Amplitude MIKAN, posted by Ronic Chiche at Optical room about lasers and optics | detectors and electronics
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MIKAN phase noise and RIN measurements:
Ronic
Chiche wrote:
Coupling into a 50-50% fiber coupler using the Thorlabs XYZ table |
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Amplitude GHz oscillator phase noise with PZT effect, posted by Ronic Chiche at Optical room about lasers and optics
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Thorlabs PZT datasheet.
Reference: PC4QR
Ronic |
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Mirrors Mottors Connections , posted by Manar Amer at Other about mechanics
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* The connections to control the motors of the mirrors are connected in the order stated :
M1
- M2 - M3 - |
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Mirrors Mottors Connections , posted by Manar Amer at Other about mechanics | cabling
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Added the cabling to the categories
Manar
Amer wrote:
* The connections to control the motors of the mirrors are connected |
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Setting up the Motors, posted by Manar Amer at Other about mechanics | cabling | software
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A document attached that describes the procedure needed to:
- connect the motors
- configure the Ethernet connection |
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Alignment using Helium Neon Laser , posted by Manar Amer at Other about lasers and optics
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| 05 April 2021 : A rough alignment of the cavity was done using the Helium Neon Laser. |
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Distances between mirrors , posted by Manar Amer at Other about mechanics | software
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At the reference zero the distance between the mirrors is (taken from a reference presentation "status9nov2020" attached):
M1-M2 = 88.029 mm
M3-M4 = 84.6895 mm |
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Alignment using Koheras , posted by Manar Amer at Other about lasers and optics 6x
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Following the Helium Neon Alignment + change in the distance between the mirrors to be; M3-M4 = 90.5 mm , M1-M2 = 80.2 mm -→ The alignment
using the Koheras CW laser is done.
Additional components used:
for monitoring beam : Photodiode (power of beam), Beam Profiler (shape, position, power |
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Mode observed and cavity Lock , posted by Manar Amer at Other about lasers and optics
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** Following up from yesterday an observation about the TM00 mode : it has been seen with similar dimensions and its position is the same, this was before
restarting the temperature regulator.
--> after restarting the temp. regulator |
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Distances between mirrors , posted by Manar Amer at Other about mechanics | lasers and optics | software
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New update on the position of the Motors for the cavity
***** we moved the motors to set the cavity at 876MHz, and checked it right after with the RF modulation at FSR.
So compared to the expected setting we had to move inwards the two planar mirrors by 0.9 mm each. |
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Mode observed and cavity Lock , posted by Manar Amer at Other about lasers and optics
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New configuration is made. The new mode observed in NF_Trans is the following :
Manar
Amer wrote:
** Following up from yesterday an observation about the TM00 mode : |
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Reflection Line Polarization Measuremet, posted by Manar Amer at Optical room about lasers and optics
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With the help of Ronic the cavity was locked in preparation to measure the polarization of the reflection line when the cavity is locked (measurement
when it is not locked was done before)
the purpose is to compare the two measurements (locked vs not locked) |
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Cameras Calibration, posted by Kevin Dupraz at Optical room about lasers and optics | detectors and electronics
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After installing cameras the actual calibration are :
NF_Refl: acA1920-40gm
pixel size (real): 5.86um |
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Cavity lock and references, posted by Kevin Dupraz at Optical room about lasers and optics | detectors and electronics
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Cavity is lock and optimized with the NKT. Input power is maximized (10mW).
Cavity mode is in attachement. The reference on camera with BeamProfiler Matlab code is the following:
FF_refl: [2.0883 1.1606] |