Cross-correlation between photons and phonons in quadratically coupled optomechanical systems

TL;DR

This paper investigates photon-phonon interactions in quadratically coupled optomechanical systems, revealing conditions for photon and phonon blockade, and demonstrating generation of correlated pairs, with implications for quantum information processing.

Contribution

It uncovers the optimal nonlinear coupling regime for photon blockade and demonstrates correlated photon-phonon pair generation in quadratically coupled systems.

Findings

Photon and phonon blockade observed in specific parameter regimes.

Optimal nonlinear coupling strength for photon blockade is not in the strong coupling regime.

Generation of correlated photon-phonon pairs with proper detuning.

Abstract

We study photon, phonon statistics and the cross-correlation between photons and phonons in a quadratically coupled optomechanical system. Photon blockade, phonon blockade and strongly anticorrelated photons and phonons can be observed in the same parameter regime with the effective nonlinear coupling between the optical and mechanical modes, enhanced by a strong optical driving field. Interestingly, an optimal value of the effective nonlinear coupling strength for the photon blockade is not within the strong nonlinear coupling regime. This abnormal phenomenon results from the destructive interference between different paths for two-photon excitation in the optical mode with a moderate effective nonlinear coupling strength. Further more, we show that phonon (photon) pairs and correlated photons and phonons can be generated in the strong nonlinear coupling regime with a proper detuning between the weak mechanical driving field and mechanical mode. Our results open up a way to generate anticorrelated and correlated photons and phonons, which may have important applications in quantum information processing.