A High Q, Quasi-Monolithic Optomechanical Inertial Sensor

In order to achieve the excellent seismic isolation necessary for the operation of gravitational wave detectors, very sensitive inertial sensors are required to measure and counteract the motion of the ground. This paper presents work on a lightweight, compact, and vacuum compatible inertial sensor based on an optomechanical design. It aims to achieve comparable noise performance to the sensors used in current gravitational wave detectors across the frequency region used for seismic isolation control, from 0.1 to 100 Hz. The quasi monolithic design of the device, along with initial measurements of the device quality factor of 28000 and the design philosophy underpinning it, are presented.