Backaction limits on self-sustained optomechanical oscillations

TL;DR

This paper investigates the maximum amplitudes and efficiencies of self-sustained optomechanical oscillations, revealing how optical backaction and cavity regimes influence these limits and the role of nonlinearities.

Contribution

It provides a combined analytical and numerical analysis of amplitude limits and quantum efficiencies in optomechanical systems, highlighting differences between cavity regimes and the impact of nonlinearities.

Findings

Quantum efficiencies >1 in resolved sideband regime

Maximum amplitude occurs in unresolved cavity regime

Mechanical nonlinearities influence oscillation limits

Abstract

The maximum amplitude of mechanical oscillators coupled to optical cavities are studied both analytically and numerically. The optical backaction on the resonator enables self-sustained oscillations whose limit cycle is set by the dynamic range of the cavity. The maximum attainable amplitude and the phonon generation quantum efficiency of the backaction process are studied for both unresolved and resolved cavities. Quantum efficiencies far exceeding one are found in the resolved sideband regime where the amplitude is low. On the other hand the maximum amplitude is found in the unresolved system. Finally, the role of mechanical nonlinearities is addressed.