I began my attempts to characterize the PDH loops at the X end today. My goal was to make the following measurements:
- Dark noise and shot noise of the PD
- Mixer noise
- Servo electronics noise
which I can then put into my simulink noise-budget scheme for the proposed IR beat setup.
I've made an Optickle model of a simple FP cavity and intend to match the measured PDH error signal from the X end to the simulated error signal to get the Hz/V calibration. I'll put the plots up for these shortly.
With regards to the other measurements, I was slowed down by remote data-acquisition from the SR785 - I've only managed to collect the analyzer noise floor data, and I plan to continue these measurements during the day tomorrow. |