R&D (FilterCavity)
MichaelPage - 00:24, Tuesday 19 December 2023 (3380)
Squeezing recovery - IR to OPO realignment

Yuhang, Chang-Hee Kim, Michael

BAB to OPO - the BAB alignment to OPO was optimized using the hom sub dc signal with one homodyne input blocked. Mode matching was increased to 1170 mV + (46, 34, 14, 18 mV) -> 91.8%. Then ppol was also aligned from a mode mismatch of about 50% and now OPO locks with ppol. However, since the OPO temperature hasn't been optimized for a long time we should re-optimize parametric gain.

PLL - there is still quite a lot of signal in the ppol PLL so probably it was not misaligned too much to the fiber (I accidentally misaligned it in pitch last time when I thought I was adjusting BAB to OPO).

Lasers - We adjusted the temperature and current for each laser to be consistent with the values in the wiki +/- 0.001

GRMC MZ - we want to measure OPO nonlinear gain by injecting green and measuring BAB transmission, but GRMC/MZ kept unlocking on short timescales for some reason. The offset for the MZ HVD was unintentionally left on by me but it should be off. But the system kept unlocking anyway. So we decided in the end to take transfer function measurement, but it was getting late, so we will do tomorrow