Enhanced Quantum Nonlinearities in a Two-Mode Optomechanical System

TLDR

Cavity optomechanics couples nanomechanical motion to a localized optical mode, and single‑photon strong coupling is achieved when a single phonon’s induced optical shift matches the cavity linewidth. The authors study a two‑optical‑mode, one‑mechanical‑mode system in this regime, analyzing quantum nondemolition detection through analytical and numerical methods. When the mechanical frequency is nearly resonant with the optical level splitting, photon‑phonon and photon‑photon interactions are markedly enhanced, enabling dispersive phonon detection and promising optomechanical photon measurement.

Abstract

In cavity optomechanics, nanomechanical motion couples to a localized optical mode. The regime of single-photon strong coupling is reached when the optical shift induced by a single phonon becomes comparable to the cavity linewidth. We consider a setup in this regime comprising two optical modes and one mechanical mode. For mechanical frequencies nearly resonant to the optical level splitting, we find the photon-phonon and the photon-photon interactions to be significantly enhanced. In addition to dispersive phonon detection in a novel regime, this offers the prospect of optomechanical photon measurement. We study these quantum nondemolition detection processes using both analytical and numerical approaches.