R&D (FilterCavity)
NaokiAritomi - 00:33, Thursday 13 February 2020 (2034)
Loss and phase noise measurement with single bounce from filter cavity

[Aritomi, Yuhang]

We locked FC with green and implemented dithering to be sure that alignment of FC is good. We locked IR off resonance (detuning is 1kHz). Unfortunately, today there was a large mode mismatch peak in AMC, which was ~50mV out of 1V. This becomes ~10% readout loss.

MZ offset green power (mW) OPO temperature  p pol PLL (MHz) CC2 demod phase (SQZ) (deg) CC2 demod phase (ASQZ) (deg)
4.2 17.4 7.163 190 185 260
4.3 21.2 7.175 200 185 260
4.4 25 7.175 200 195 255
4.6 32.6 7.2 215 200 255
4.8 39 7.2 200 195 250
5.2 50.5 7.22 200 200 250
4.8 (without OD 0.2) 57 7.22 180 195 240

Measured loss is 40(1) % and phase noise is 30(5) mrad.

Images attached to this report
2034_20200212163307_sqzasqz20200212.png