David Notebook: Difference between revisions

I've abandoned the [[Thorlabs PDA10A Si Amplified Fixed Detector|Thorlabs PDA10A]] in favor of the [[Thorlabs PDA36A Si Switchable Gain Detector|Thorlabs PDA36A]]. It's fast enough to produce square waves at 400 Hz, and has a much larger sensor. It also has a lower minimum gain, which seems to work better when used in conjunction with the lock-in. I still should try to check if the response is linear at low powers. Ostensibly though, using it's different gain/sensisitivty values and following the same analysis from 7/18/14, I get about 3.2 nW of chopped 633 power at the detector. This is still an efficiency of around <math> 6*10^{-7}</math> although it looks much brighter than before. Maybe one set of power measurements is somewhat inaccurate. I really don't trust the photodiodes to gives accurate linear responses at such low laser powers.