Wavelength-sized GaAs optomechanical resonators with GHz frequency

TL;DR

This paper presents wavelength-sized GaAs optomechanical disk resonators with GHz frequency, demonstrating ultra-strong optomechanical coupling, high sensitivity, and optical transduction of mechanical modes at room temperature.

Contribution

The study introduces GaAs optomechanical disk resonators with record optomechanical coupling rates and GHz frequencies, advancing integrated optomechanics.

Findings

Optical transduction of 1.4 GHz mechanical mode

Vacuum optomechanical coupling rate of 0.8 MHz

Sensitivity of 10^-17 m/√Hz at room temperature

Abstract

We report on wavelength-sized GaAs optomechanical disk resonators showing ultra-strong optomechanical interaction. We observe optical transduction of a disk mechanical breathing mode with 1.4 GHz frequency and effective mass of ~ 2 pg. The measured vacuum optomechanical coupling rate reaches 0.8 MHz, with a related differential optomechanical coupling factor of 485 GHz/nm. The disk Brownian motion is optically resolved with a sensitivity of 10-17 m/{\sqrt}Hz at room temperature and pressure.