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Entry   PW laser Injection into cavity , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics 20230412_pulsed_cav_mode.bmp
    Reply   PW laser Injection into cavity , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics 20230418_size_of_beam_before_injection_window_at_10percetage_ampli.jpg20230418_coupling_at_the_start_only_alignment_improved1.jpg20230418_zoom_on_Oscilliscope_signal_fundamental_mode.jpg20230418_coupling_after_improving_it_with_regulator_on_attempting_to_lock.jpg
       Reply   PW laser Injection into cavity , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics 
          Reply   PW laser Injection into cavity , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics 2023-05-22_MMD3_error_on_alarm_window.jpg2023-05-22_alphanov_software.jpg
             Reply   Cavity Lock - Alphanov Amplifier , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics | cabling | software tek00000.png
                Reply   Cavity Lock - Alphanov Amplifier , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics | cabling | software 13x
                   Reply   Cavity Lock - Alphanov Amplifier , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics | cabling | software 20230605_tek00001_33uW.png20230605_tek00002_82uW.png
                      Reply   Cavity Lock - Alphanov Amplifier , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics | cabling | software tek00001.png20230607_183626_Frep_CEP_motors_smartAct.jpg20230607_183641_transmitted_power.jpgtek00002.png
                         Reply   Cavity Lock - Alphanov Amplifier , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics | cabling | software tek00001_noise_reduced_first_resonance.pngtek00000_cavity_lock_with_noise_from_odcillator_controller.png
                            Reply   Cavity Lock - Alphanov Amplifier , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics | cabling | software 
Message ID: 209     Entry time: Wed Apr 19 16:39:28 2023     In reply to: 208     Reply to this: 210
 Author: Manar Amer 
 Status: Fixed 
 Type: report 
 Category: lasers and optics | detectors and electronics 
 Location: ThomX igloo 
 Title: PW laser Injection into cavity  
  • On Monday with Daniele,
    • we did full characterization of amplifier beam @ 10% amplification, adjusted the telescope accordingly and injected into the cavity aligned and improved on the fundamental mode.
  • On Tuesday with Daniele and Kevin
    •  I added a low pass filter between 1 - 1.9 MHz on the reflected signal, to reject the oscillator signal (33.33 MHz)
    • removed the external resistors on the signal, only the internal resistance of the oscilloscope used ( transmission : 1 M ohm  , Reflection : 50 ohm  )
    • We connected the motors to control the CEP and adjusted on them until we reached ~ 5 -10% coupling
  • Images:
    • 1st : showing the size of the beam just before injecting into the cavity @ 10%
    • 2nd: signal with only improved alignment (not CEP adjustment yet), no low pass filter added yet
    • 3rd : zoom on the signals (reflection and error) while adjusting on the CEP
    • 4th :attempting to lock the cavity , after getting the max coupling using the CEP motors

Note : the voltage ranges are not the same between the images

Manar Amer wrote:

Yesterday,

  • we installed the second high power reflecting mirrors at the output of the amplifier.
  • We aligned and installed a telescope that has adjustable distance between the 2 lenses of -100 mm, and + 200 mm, with approximate diameter at the injection window of  ~ 4.5 mm.
  • Amplifier was turned on only at the first stage only (output power ~ 300 mW) aligned and injected into the cavity.
  • Measured the repetition frequency of the One Five oscillators, Frep = 33.326239 MHz
  • Changed the FSR of the cavity to match it.
  • Using the Piezo scan on the oscillator, we observed 00 Mode, Fundamental. the shape is the same 
  • We see transmission on the diode, but there was zero coupling observed (yet to be investigated experimentally )
    • a reason could be the CEP of the oscillator ,
    • bad matching of the beam waist position,
    • noise from the amplifier (as we were operating it at very low power)
    • additional alignment needed,

 

Attachment 1: 20230418_size_of_beam_before_injection_window_at_10percetage_ampli.jpg  56 kB  | Hide | Hide all | Show all
20230418_size_of_beam_before_injection_window_at_10percetage_ampli.jpg
Attachment 2: 20230418_coupling_at_the_start_only_alignment_improved1.jpg  74 kB  | Hide | Hide all | Show all
20230418_coupling_at_the_start_only_alignment_improved1.jpg
Attachment 3: 20230418_zoom_on_Oscilliscope_signal_fundamental_mode.jpg  74 kB  | Show | Hide all | Show all
Attachment 4: 20230418_coupling_after_improving_it_with_regulator_on_attempting_to_lock.jpg  76 kB  | Hide | Hide all | Show all
20230418_coupling_after_improving_it_with_regulator_on_attempting_to_lock.jpg
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