I've updated the PSOMA optical layout. I still have some questions on locking, and there are a few additional configurations that we could try. In particular:
Each of these configurations also has a couple different ways to pickoff an LO for homodyne readout. Shruti and I enumerated these configurations on a zoom whiteboard a couple weeks ago, and I've attached them (the zip contains png).
Chris also mentioned last week that we may run into a frequency-dependent loss in the critically coupled cavity configurations. The pdf I've attached shows a configuration that I think is a minimal modification of the Mach-Zehnder amplifier described in PSOMA. One of the ring cavities is replaced with a tunable steering mirror, and the LO is picked off before the pump reaches the MZ.
In the new diagram, I'm thinking about controlling the following degrees of freedom:
Some things I'm unsure about:
Shruti and I are now tracking our work on git issues in the PSOMA repo.