[Huyen, Shoshana]

We saw worsening CRS noise after adding copper block on top of the laser in an attempted to help with thermal regulation. We went ahead and removed the copper block and saw that the noise improved significantly.

Picture one shows the noise taken over the weekend with copper block on the laser (with capacitive damping on) [ref], and the noise during the day right after the block was removed (with capacitive damping on).

When removing the copper we noticed it was pretty cool to the touch, so it probably wasn't providing much thermal regulation to begin with (i.e. the TEC is doing it's job). Our best guess for why it was worsening the noise is that having some extra weight on the laser was adding some extra stress onto it which was translating to the signal.

Since getting the capacitive damping hooked up, we've been keeping the gain at 100, which seems to damp down the CRS at a reasonable rate without putting to much voltage on it, and we decrease the gain to 50 once the  CRS is relatively damped down.