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Entry  Thu Aug 28 13:40:05 2014, Evan, DailyProgress, FSS, PDH error signal on north cavity npdh_broad.pdfnpdh_fine.pdfnpdh_sweep.zip
    Reply  Thu Aug 28 20:47:24 2014, Evan, DailyProgress, FSS, PDH error signal on north cavity npdh_sim.pdfnpdh_sim_narrow.pdffpbirefringence.pdf
       Reply  Fri Aug 29 09:21:26 2014, Evan, DailyProgress, FSS, PDH shot noise estimate noiseBudget.pdf
Message ID: 1491     Entry time: Fri Aug 29 09:21:26 2014     In reply to: 1490
Author: Evan 
Type: DailyProgress 
Category: FSS 
Subject: PDH shot noise estimate 

Ignoring for the time being the issue of offsets in the PDH error signal, here's my prediction for the new PDH shot noise level, assuming a visibility of 0.92 × 0.7 = 0.64 and an incident power of 2 mW.

So our beat will be slightly worse around 1 kHz, but we aren't completely hosed by the shot noise. I'd think the true solution here is to find (or buy) two large-aperture Faraday isolators to replace the PBS+QWP setup (according to alm, the spot size in this region is about 1.1 mm). E.g., we might consider a large-aperture ThorLabs isolator.

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