Parametrically Driven Inertial Sensing in Chip‐Scale Optomechanical Cavities at the Thermodynamical Limits with Extended Dynamic Range

Abstract

AbstractRecent scientific and technological advances have enabled the detection of gravitational waves, autonomous driving, and the proposal of a communications network on the Moon (Lunar Internet or LunaNet). These efforts are based on the measurement of minute displacements and their corresponding force transduction, which enables acceleration, velocity, and position determination for navigation. State‐of‐the‐art accelerometers use capacitive or piezoresistive techniques and micro‐electromechanical systems (MEMS) via integrated circuit (IC) technologies to drive transducers and convert their output for electric readout. In recent years, laser optomechanical transduction and readout have enabled highly sensitive detection of motional displacement. Here the theoretical framework is further examined for the novel mechanical frequency readout technique of optomechanical transduction when the sensor is driven into oscillation mode. Theoretical and physical agreements are demonstrated, and the most relevant performance parameters are characterized by a device with a 1.5 mg Hz−1 acceleration sensitivity, a 2.5 fm Hz−1/2 displacement resolution corresponding to a 17.02 µg Hz−1/2 force‐equivalent acceleration, and a 5.91 Hz nW−1 power sensitivity, at the thermodynamical limits. In addition, a novel technique is presented for dynamic range extension while maintaining the precision sensing sensitivity. This inertial accelerometer is integrated on‐chip and enabled for packaging, with a laser‐detuning‐enabled approach.