Comparing nonlinear optomechanical coupling in membrane-in-the-middle and single-cavity optomechanical systems

TL;DR

This paper compares nonlinear optomechanical coupling in membrane-in-the-middle and single-cavity systems, revealing limitations in enhancement and selectivity, and discusses potential applications in quantum state engineering.

Contribution

It provides a direct comparison of nonlinear optomechanical effects in MIM and single-cavity systems, highlighting constraints and potential advantages for quantum applications.

Findings

Enhancement of nonlinearity in MIM is limited by sideband resolution.

Nonlinear selectivity in MIM matches that of single-cavity systems.

Dynamical backaction effects are similar per photon, with reduced power requirements.

Abstract

In cavity optomechanics, nonlinear interactions between an optical field and a mechanical resonator mode enable a variety of unique effects in classical and quantum measurement and information processing. Here, we describe nonlinear optomechanical coupling in the membrane-in-the-middle (MIM) setup in a way that allows direct comparison to the intrinsic optomechanical nonlinearity in a standard, single-cavity optomechanical system. We find that the enhancement of nonlinear optomechanical coupling in the MIM system as predicted by Ludwig et al. arXiv:1202.0532 is limited to the degree of sideband resolution of the system. Moreover, we show that the selectivity of the MIM system of nonlinear over linear transduction has the same limit as in a single cavity system. These findings put constraints on the experiments in which it is advantageous to use a MIM system. We discuss dynamical backaction effects in this system and find that these effects per cavity photon are exactly as strong as in a single cavity system, while allowing for reduction of the required input power. We propose using the nonlinear enhancement and reduced input power in realistic MIM systems towards parametric squeezing and heralding of phonon pairs, and evaluate the limits to the magnitude of both effects.