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Entry   CELIA amplifier installation, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software 
The amplifier was installed on the optical table next to SBox table.

The CVBG that will be used for stretching before amplification needs cleaning (they are very fragile, 'ask victor for best method')

The software to drive the diodes of the amplifier we have is not the compatible one.
    Reply   CELIA amplifier installation + chiller, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software WhatsApp_Image_2022-07-22_at_4.26.24_PM.jpgWhatsApp_Image_2022-07-22_at_4.26.24_PM.jpgWhatsApp_Image_2022-07-22_at_5.02.24_PM.jpg
Amplifier placed next to the pulsed laser on the table under the airflow

The output is in free space with height from the table of about 10 cm, note the injection height into the cavity is between 14 - 15 cm.

a power cable is placed but not plugged.
Entry   Alignment / Table setup , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software 20220722_table_setup.jpg20220722_tablesetup.jpg
The current setup of the optical table attached.

The cavity is aligned and the lock of the fundamental mode has been attempted, but the mode is drifting too quickly to be able to follow.

I have placed the cavity under vacuum for a better stability.
Entry   CVBG stretching / Fiber Injection , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software 7x
Before injecting into the amplifier, the pulse needs to be stretched using a CVBG, type attached.

the CVBG is to be used at a small angle, the beam shape and spectrum after the PBS is attached.

After measuring the beam profile, a mirror was placed to direct all the power for fiber injection
    Reply   CELIA amplifier installation + chiller, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software 
The software to control the CELIA amplifier is on the laptop that was placed in ThomX bunker.

I have placed it in the PLIC room next to the SBox table.

it is called 'Alphanov Control Software'
    Reply   CELIA amplifier installation + chiller, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software 
Closing series




Manar
Amer wrote:



The software to control the CELIA amplifier is on the laptop that was
    Reply   Alignment / Table setup , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software 
closing series




Manar
Amer wrote:



The current setup of the optical table attached.
    Reply   CVBG stretching / Fiber Injection , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics | software 
closing series




Manar
Amer wrote:



Before injecting into the amplifier, the pulse needs to be stretched
Entry   OEwaves CW Laser - Phase Noise , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 20210207_OEwaves_laser.jpg20210207_Self_coupling_setup.jpgSchematic-setup-for-optical-delayed-self-coupling-detection.png

We started measuring the phase noise on the OEwaves CW laser.

Class 3b
wavelength 1.5 um


The
procedure is done using self coupling of the laser

splitter 50%-50%\
delay line 100 m 
all fibers are PM type
(polarity maintained)
Photodetector is "lab buddy", very fast diode.
Note: différance from schematic (we did not
    Reply   OEwaves CW Laser - Phase Noise , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 
a correction on the wavelength of the laser  it is 1030 um 




Manar
Amer wrote:




We started measuring the phase noise on the OEwaves CW laser.

Class
    Reply   OEwaves CW Laser - Phase Noise , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 
correction on unit 1030 nm




Manar
Amer wrote:



a correction on the wavelength of the laser  it is 1030 um 
Entry   2 Mirror Setup @ 216.6 MHz, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 20220706_Setup.jpgScreenshot_2022-07-06_1_181116.pngFinesse_Fit.jpg00mode.jpg00mode_diameter.jpg
The SBox cavity setup was changed to have only 2 mirrors M1 plane and M2 spherical, both from ThomX

Distance between the mirror ~ 72 cm , increased from 70 cm to take into account the thickness of the ThomX mirrors

Two lenses (300 mm @ 50 cm , 200 @ 104 cm) were placed to have the beam radius ~ 0.55 mm.
    Reply   2 Mirror Setup @ 216.6 MHz, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 00mode.jpg00mode_diameter.jpgScreenshot_2022-07-08_0_164115.pngSlide1.JPGSlide2.JPG
The cavity was realigned using irises instead of pinholes, gave a better alignment.

The inside of the box, the spherical and the injection mirror were cleaned and placed back inside the box.

we see beating of fundamental mode, previously at the transmission point we placed a wedge to split the beam which resulted in an elliptical
    Reply   2 Mirror Setup @ 216.6 MHz, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics Screenshot_2022-07-08_2_182405.png
Update for Finesse measurement, The cavity was put under vacuum ~ 1.1*10^-1 mbar

and the alignment and coupling improved.

FSR = 210.1 MHz
    Reply   FSR change & Finesse Measurements , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 00mode.jpg00mode_diameter.jpg00mode_diameter_fit.jpg
The FSR of the 2 mirror (plan-spherical) Cavity was adjusted from 210 MHz to reach 216.643 MHz

it was done by having two reference irises, one at the injection point and one at the reflection 

then changing the position of injection plan mirror to slightly closer distance and monitoring the reflection on the oscilloscope to be max.
    Reply   FSR change & Finesse Measurements , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics Screenshot_2022-07-11_1_204143.pngScreenshot_2022-07-11_0_203646.png
Yesterday evening the cavity was Vacuum pumped up to pressure of 5.5*10^-2 and locked 

changed FSR to be 216.662 MHz and alignment a little and measured the Finesse

in Vacuum we have average Finesse = 30341.6265
    Reply   FSR change & Finesse Measurements , posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 
a Finesse of 30k with the present mirrors :

T1=120 ppm ;A1=(2.6+1) ppm;
T2=1.5 ppm ;A2=(4.5+0.27) ppm;
    Reply   Installation of D-shaped mirror / Alignment, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 
To prepare for the amplifier. I installed the D-shapped mirrors after cleaning (using aceton and ethanol) between the cavity 2 mirrors.

Before closing, I observed the back reflection from M1 (injection mirror). both the injection and reflection lines were off, due to that there
was an internal reflection hitting the walls of the cavity.
    Reply   Installation of D-shaped mirror / Alignment, posted by Manar Amer at Optical room about lasers and optics | detectors and electronics 
The D-shaped mirrors are installed properly and not cutting the path of the beam.

The cavity has been aligned again and 00 modes beating observed, and external reference points has been placed.




Manar
Entry   Koheras CW laser lock on FP cavity, posted by Ronic Chiche at Optical room about lasers and optics | detectors and electronics 
I locked the Koheras CW on the FP cavity but the lock was pretty noisy and very difficult to acquire.

I tried to produce some modulation sidebands close to 216MHz to measure the Finesse but the power loss was very small so, the signal to extract
the Finesse would be unreadable !
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