[Aritomi, Yuhang]
First we measured nonlinear gain again. We measured BAB transmission from OPO. When we used 40mW green, we decreased CC1 gain from 2 to 1.
| green power (mW) | BAB maximum (V) | OPO temperature (kOhm) | p pol PLL (MHz) |
| 0 | 0.0552 | 7.194 | 305 |
| 40.9 | 1.02 | 7.194 | 195 |
The measured nonlinear gain is 18.5 with 40.9 mW green while the theoretical value should be g = 1/(1-sqrt(40.9/80))^2 = 12.3. We don't know why they are different.
We found an oscillation in FC lock with green injection of 27mW and FC gain of 1.3. The green injection power was larger so we decreased FC gain from 1.3 to 1.
We measured CCFC with 40.9 mW pump green and 50% pick off. Fig 1 shows the CCFC error signal with some demodulation phase and Fig 2 shows CCFC calibration signal when CCSB are off resonance and CC1 is scanned. The amplitude of CCFC calibration signal is 524mVpp which is 10 times larger than before.
We will try with 20% pick off and thorlabs BSS11 seems good for BS (20% reflection for p pol).
