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groups:mg:experiment:laser:457nmlaser [2016/04/20 15:42] – klausgroups:mg:experiment:laser:457nmlaser [2016/04/20 15:43] (current) – klaus
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   * Max outpupower: 200 mW   * Max outpupower: 200 mW
  
-== Doublepass AOM (for Wutz)+== Doublepass AOM (for Wutz) ==
   * Modulation frequency: 104.674 MHz @ 7 dBm (1.7.2013)   * Modulation frequency: 104.674 MHz @ 7 dBm (1.7.2013)
   * Diffraction Order: 2 x -1   * Diffraction Order: 2 x -1
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 == Wutz Resonator == == Wutz Resonator ==
-  * EOM frequency: 9.7 MHz @ 15 dbM+  * EOM frequency: 9.7 MHz @ 15 dBm
   * After fiber: ~ 300 µW   * After fiber: ~ 300 µW
   * Infront of iris next to resonator: ~ 200 µW   * Infront of iris next to resonator: ~ 200 µW
  
 === Wutz Resonator Adjustment === === Wutz Resonator Adjustment ===
-=If there is no light coupled into the resonator=+ 
 +==If there is no light coupled into the resonator==
 Adjust the beam with the mirror on the periscope so it passes the iris after that mirror. Then use the second mirror so the backreflected light overlaps with the incoming light. Alternatively, adjust the beam so it hits the center of the iris on the PDH photodiode. Modes should be visible now. Adjust the beam with the mirror on the periscope so it passes the iris after that mirror. Then use the second mirror so the backreflected light overlaps with the incoming light. Alternatively, adjust the beam so it hits the center of the iris on the PDH photodiode. Modes should be visible now.
-=Finding and optimizing TEM00=+ 
 +==Finding and optimizing TEM00==
 Search for the smallest TEMnm mode you can find and lock the resonator too. Optimize the incoupling via the two incoupling mirrors by increasing the signal of the transmission photodiode. Search for the smallest TEMnm mode you can find and lock the resonator too. Optimize the incoupling via the two incoupling mirrors by increasing the signal of the transmission photodiode.
 Now search for a smaller TEMnm mode and repeat the process until you can see/lock to TEM00. Now search for a smaller TEMnm mode and repeat the process until you can see/lock to TEM00.
 As a tip: Sometimes it is helpful to set the laser to scan mode and keep the lock enabled (without piezo-lock/integrator). Modes will occasionally be locked. Now adjust these "peaks". As a tip: Sometimes it is helpful to set the laser to scan mode and keep the lock enabled (without piezo-lock/integrator). Modes will occasionally be locked. Now adjust these "peaks".
  
-=Adjusting RAM-compensation=+==Adjusting RAM-compensation==
 Residual amplitude modulation happens when the input polarization of the EOM is incorrect (waveplate incorrect/temperature drifts) or residual etalons in the EOM are present (adjustment through EOM under biggest angle to reduce etalons). Residual amplitude modulation happens when the input polarization of the EOM is incorrect (waveplate incorrect/temperature drifts) or residual etalons in the EOM are present (adjustment through EOM under biggest angle to reduce etalons).