Continuation Sheet ) Continuation for Block 13 ARO Report

Pump frequency noise coupling into a microcavity by thermo-optic locking Report Title As thermo-optic locking is widely used to establish a stable frequency detuning between an external laser and a high Q microcavity, it is important to understand how this method affects microcavity temperature and frequency fluctuations. A theoretical analysis of the laser-microcavity frequency fluctuations is presented and used to find the spectral dependence of the suppression of laser-microcavity, relative frequency noise caused by thermo-optic locking. The response function is that of a high-pass filter with a bandwidth and low-frequency suppression that increase with input power. The results are verified using an external-cavity diode laser and a silica disk resonator. The locking of relative frequency fluctuations causes temperature fluctuations within the microcavity that transfer pump frequency noise onto the microcavity modes over the thermal locking bandwidth. This transfer is verified experimentally. These results are important to investigations of noise properties in many nonlinear microcavity experiments in which lowfrequency, optical-pump frequency noise must be considered. Pump frequency noise coupling into a microcavity by thermo-optic locking Approved for public release; distribution is unlimited. 65981.2-PH-DRP REPORT DOCUMENTATION PAGE (SF298) (Continuation Sheet) Continuation for Block 13