Nonlinear interaction effects in a strongly driven optomechanical cavity

TL;DR

This paper investigates how nonlinear effects in a strongly driven optomechanical cavity can be significantly enhanced and observed through modifications in the cavity density of states and nonclassical photon correlations.

Contribution

It introduces a Keldysh Green's function approach to analyze nonlinear interaction effects and proposes experimental methods to detect these effects in optomechanical systems.

Findings

Strong modifications to the cavity density of states can occur even with weak nonlinear interactions.

Enhanced nonlinear interactions can induce nonclassical photon correlations.

Proposed experimental setup for observing these effects via optomechanically-induced transparency.

Abstract

We consider how nonlinear interaction effects can manifest themselves and even be enhanced in a strongly driven optomechanical system. Using a Keldysh Green's function approach, we calculate modifications to the cavity density of states due to both linear and nonlinear optomechanical interactions, showing that strong modifications can arise even for a weak nonlinear interaction. We show how this quantity can be directly probed in an optomechanically-induced transparency type experiment. We also show how the enhanced interaction can lead to nonclassical behaviour, as evidenced by the behaviour of g_2 correlation functions.