[Enomoto, Sugimoto]

Today, we achieved phase lock a Y arm Prometheus to the main laser.

We locked the beat-note frequency to 50 MHz.

The servo settings are the same as X, but we only used a PZT control loop, since BNC port for temperature control of laser couldn't use.

First figure is the control signal and error signal when locked, and second figure is the transfer function of the control loop measured.