Floquet scattering of light and sound in Dirac optomechanics

TL;DR

This paper explores how laser-driven quantum dots in a honeycomb optomechanical array enable inelastic photon-phonon scattering, revealing regimes for polariton formation and potential applications as a quantum transistor for light and sound.

Contribution

It introduces a Floquet theory approach to analyze inelastic scattering in Dirac optomechanics beyond the rotating-wave approximation.

Findings

Identification of different scattering regimes

Formation of polaritonic quasiparticles

Conditions for observing zitterbewegung

Abstract

The inelastic scattering and conversion process between photons and phonons by laser-driven quantum dots is analyzed for a honeycomb array of optomechanical cells. Using Floquet theory for an effective two-level system, we solve the related time-dependent scattering problem, beyond the standard rotating-wave approximation approach, for a plane Dirac-photon wave hitting a cylindrical oscillating barrier that couples the radiation field to the vibrational degrees of freedom. We demonstrate different scattering regimes and discuss the formation of polaritonic quasiparticles. We show that sideband-scattering becomes important when the energies of the sidebands are located in the vicinity of avoided crossings of the quasienergy bands. The interference of Floquet states belonging to different sidebands causes a mixing of long-wavelength (quantum) and short-wavelength (quasiclassical) behavior, making it possible to use the oscillating quantum dot as a kind of transistor for light and sound. We comment under which conditions the setup can be utilized to observe zitterbewegung.