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Entry  Fri Jan 4 19:04:29 2019, awade, DailyProgress, RFAM, Time to look at RF AM and RIN 
    Reply  Wed Jan 9 17:25:38 2019, anchal, DailyProgress, RFAM, Time to look at RF AM and RIN RIN_DBN_Coherence_Measurement.pdf
       Reply  Wed Jan 9 19:05:56 2019, anchal, DailyProgress, RFAM, Time to look at RF AM and RIN 
          Reply  Thu Jan 10 11:38:53 2019, awade, DailyProgress, RFAM, Time to look at RF AM and RIN 
             Reply  Thu Jan 10 17:30:24 2019, anchal, DailyProgress, RFAM, Time to look at RF AM and RIN 
                Reply  Thu Jan 10 18:52:20 2019, anchal, DailyProgress, RFAM, Time to look at RF AM and RIN 
                   Reply  Sat Jan 12 13:11:02 2019, awade, DailyProgress, RFAM, Time to look at beatnote after RF AM and RIN tuneup 
                      Reply  Wed Jan 16 11:07:41 2019, anchal, DailyProgress, NoiseBudget, Beatnote after RF AM and RIN tuneup LaserPowerNoise_to_BNFreqNoise_TF.pdfIN_to_BN_TF.zipTransmission_RIN_Jan15_2019.pdfRIN_Measurement_20190115.zip20190116_130937noiseBudget.pdf
    Reply  Thu Jan 10 14:19:46 2019, anchal, DailyProgress, RFAM, Time to look at RF AM and RIN 
Message ID: 2279     Entry time: Thu Jan 10 14:19:46 2019     In reply to: 2273
Author: anchal 
Type: DailyProgress 
Category: RFAM 
Subject: Time to look at RF AM and RIN 

I found this paper on OSA: Control of residual amplitude modulation in Lithium Niobate phase modulators. It suggests a control mechanism which does not require controlling the temperature. The main point in it is that if a DC offset is present in the RF signal going into the EOM, it is effectively the same as changing the temperature by some amount. So, in principle, by changing the DC bias of the RF signal with a bias-tee just before the EOM, one can minimize the RF AM modulation. The paper though doesn't suggest the feedback mechanism or what sensor would be good for this. If we think this is worth giving a shot, in my opinion, if we fork the output of EOM somehow, measure the RFAM through it and employ a feedback circuit to control the DC offset, we can actively suppress the RFAM. Just a thought at this moment.


Just after writing above, I realized people at JILA have done something similar (with more complexity though):
Reduction of residual amplitude modulation to 1 × 10-6 for frequency modulation and laser stabilization

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