[Aritomi, Yuhang]
First we measured squeezing when filter cavity is locked/unlocked (Pic. 1). We expected more squeezing since we improved reflectivity of dichroic mirror by 4%, but squeezing level is still around 6.1dB when filter cavity is unlocked. Squeezing level when filter cavity is locked/unlocked is similar, but phase noise seems suppressed when filter cavity is locked.
Here are some information of this measurement.
green power (mW) | OPO temperature (kOhm) | p pol PLL (MHz) | Demodulation phase of CC2 (SQZ) (deg) | Demodulation phase of CC2 (ASQZ) (deg) |
40 | 7.19 | 165 | 105 | 135 |