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Entry  Sat Jan 6 05:18:12 2018, Kevin, Update, PonderSqueeze, Displacement requirements for short-term squeezing displacement_noise.pdfnoise_budget.pdf
    Reply  Sat Jan 6 13:47:32 2018, rana, Update, PonderSqueeze, Displacement requirements for short-term squeezing 
       Reply  Sat Jan 6 23:25:18 2018, Kevin, Update, PonderSqueeze, Displacement requirements for short-term squeezing displacement_noise.pdfnoise_budget.pdfangles.pdf
          Reply  Sun Jan 7 03:22:24 2018, Koji, Update, PonderSqueeze, Displacement requirements for short-term squeezing 
             Reply  Sun Jan 7 11:40:58 2018, Kevin, Update, PonderSqueeze, Displacement requirements for short-term squeezing 
                Reply  Sun Jan 7 17:27:13 2018, gautam, Update, PonderSqueeze, Displacement requirements for short-term squeezing 
                   Reply  Sun Jan 7 20:11:54 2018, Koji, Update, PonderSqueeze, Displacement requirements for short-term squeezing 
                      Reply  Thu May 3 00:42:38 2018, Kevin, Update, PonderSqueeze, Coil driver contribution to squeezing noise budget 
Message ID: 13508     Entry time: Sat Jan 6 05:18:12 2018     Reply to this: 13509
Author: Kevin 
Type: Update 
Category: PonderSqueeze 
Subject: Displacement requirements for short-term squeezing 

I have been looking into whether we can observe squeezing on a short timescale. The simulations I show here say that we can get 2 dBvac of squeezing at about 120 Hz using extreme signal recycling.

The parameters used here are

  • 100 ppm transmissivity on the folding mirrors giving a PRC gain of 40.
  • 10 kΩ series resistance for the ETMs; 15 kΩ series resistance for the ITMs.
  • 1 W incident on the back of PRM.
  • PD quantum efficiency 0.88.

The first attachment shows the displacement noise. The red curve labeled vacuum is the standard unsqueezed vacuum noise which we need to beat. The second attachment shows the same noise budget as a ratio of the noise sources to the vacuum noise.

This homodyne angle and SRC detuning give about the maximum amount of squeezing. However, there's quite a bit of flexibility and if there are other considerations, such as 100 Hz being too low, we should be able to optimize these angles (even with more pessimistic values of the above parameters) to see at least 0.2 dBvac around 400 Hz.

Attachment 1: displacement_noise.pdf  22 kB  | Hide | Hide all
displacement_noise.pdf
Attachment 2: noise_budget.pdf  21 kB  | Hide | Hide all
noise_budget.pdf
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