Optomechanical gyroscope simultaneously estimating the position of the rotation axis

Abstract

We realize that an optomechanical system is not only able to measure angular velocity, but also simultaneously estimate position of the corresponding rotation axis. To implement the simultaneous estimation, we first propose a multiparameter estimation scheme through a system that consists of two optomechanical subsystems. The angular velocity and rotation-axis position are jointly sensed by tested mass and then estimated by radiation exiting from the cavity due to optomechanical coupling. We adequately consider the nuisance angles, which arise from unexpected misalignment of the system, and cavity decay and provide the precision bound of the homodyne detection. The results that reveal a phase-sensitive effect indicate that selecting an appropriate phase can improve precision. Our scenario and the corresponding analysis provide a possibility to optimize rotation estimation.