Compact Modeling and Behavioral Simulation of an Optomechanical Sensor in Verilog A

Abstract

Previous work has shown that optomechanical resonators are particularly well suited to the design of ultrasensitive mass sensors. They present an extremely low noise level, very high optical quality factor ( ${Q}>{10}^{5}$ ), excellent integration density and can resonate both in a gaseous and liquid environment. In order to reduce the long measurement time due to their small particle-capture area, several such resonators must be integrated onto the same chip. However, bulky laboratory equipment currently used to read a single optomechanical resonator cannot be practically scaled up to a large array of transducers. It is then required to design and eventually integrate a read-out interface that can process tens to thousands of resonators. To ease the design of such a circuit, this article presents a compact analytical model of an electrostatically actuated optomechanical resonator implemented in Verilog A. The proposed model includes both the optical and mechanical behaviors, as well as optomechanical coupling and thermo-optical effect. It was simulated in the Cadence Virtuoso environment and is consistent with the measured results.