Generation and detection of non-Gaussian phonon-added coherent states in optomechanical systems

TL;DR

This paper proposes a scheme to generate and detect non-Gaussian phonon-added coherent states in optomechanical systems, enabling the observation of nonclassical properties of mechanical motion with existing technology.

Contribution

It introduces a full scheme for preparing and verifying non-Gaussian phonon-added coherent states in mechanical oscillators within cavity optomechanics.

Findings

Successful generation of non-Gaussian phonon-added states

Verification of nonclassical properties like sub-Poissonian statistics

Scheme is compatible with current optomechanical devices

Abstract

Adding excitations on a coherent state provides an effective way to observe nonclassical properties of radiation fields. Here we describe and analyse how to apply this concept to the motional state of a mechanical oscillator and present a full scheme to prepare non-Gaussian {\it phonon}-added coherent states of the mechanical motion in cavity optomechanics. We first generate a mechanical coherent state using electromagnetically induced transparency. We then add a single phonon onto the coherent state via optomechanical parametric down-conversion combined with single photon detection. We validate this single-phonon-added coherent state by using a red-detuned beam and reading out the state of the optical output field. This approach allows us to verify nonclassical properties of the phonon state, such as sub-Poissonian character and quadrature squeezing. We further show that our scheme can be directly implemented using existing devices, and is generic in nature and hence applicable to a variety of systems in opto- and electromechanics.