Nonclassical mechanical states in cavity optomechanics in the single-photon strong-coupling regime

TL;DR

This paper demonstrates that in cavity optomechanics under strong coupling, transient dynamics driven by an optical field can produce nonclassical mechanical states with negative Wigner functions, even with weak dissipation.

Contribution

It reveals the generation of nonclassical mechanical states during transient dynamics in the strong coupling regime, highlighting the role of optical drive and analytical insights into superposition states.

Findings

Strong coupling induces nonclassical states with negative Wigner functions.

Transient states are superpositions of coherent states.

Wigner negativity persists under weak dissipation.

Abstract

Generating nonclassical states of mechanical systems is a challenge relevant for testing the foundations of quantum mechanics and developing quantum technologies. Significant effort has been made to search for such states in the stationary behaviour of cavity optomechanical systems. We focus instead on the transient dynamics. We find that in the strong coupling regime the presence of an optical drive causes an initial mechanical coherent state to evolve to a nonclassical state, with strongly negative Wigner function. An analytical treatment for weak drive reveals that these states are quantum superpositions of coherent states. Numerical simulation shows that the presence of Wigner negativity is robust against weak dissipation.