Nonlinear effects in modulated quantum optomechanics

TL;DR

This paper introduces a method to achieve nonlinear quantum effects in weakly coupled optomechanical systems through modulation, enabling phenomena like photon blockade and nonclassical state generation.

Contribution

The authors propose a modulation-based approach to enhance optomechanical interactions into the strong-coupling regime, facilitating nonlinear quantum effects in weakly coupled systems.

Findings

Resonant optomechanical interaction is effectively enhanced via modulation.

Phonon noise can be suppressed with a squeezed vacuum reservoir.

Photon blockade and nonclassical states are realizable in weakly coupled systems.

Abstract

The nonlinear quantum regime is crucial for implementing interesting quantum effects, which have wide applications in modern quantum science. Here we propose an effective method to reach the nonlinear quantum regime in a modulated optomechanical system (OMS), which is originally in the weak-coupling regime. The mechanical spring constant and optomechanical interaction are modulated periodically. This leads to the result that the resonant optomechanical interaction can be effectively enhanced into the single-photon strong-coupling regime by the modulation-induced mechanical parametric amplification. Moreover, the amplified phonon noise can be suppressed completely by introducing a squeezed vacuum reservoir, which ultimately leads to the realization of photon blockade in a weakly coupled OMS. The reached nonlinear quantum regime also allows us to engineer the nonclassical states (e.g., Schr\"{o}dinger cat states) of cavity field, which are robust against the phonon noise. This work offers an alternative approach to enhance the quantum nonlinearity of an OMS, which should expand the applications of cavity optomechanics in the quantum realm.