Shaping Dynamical Casimir Photons

TL;DR

This paper explores the space-time dynamical Casimir effect, demonstrating how spatio-temporal modulation of systems can generate entangled photon pairs with controllable properties, advancing quantum photonics and vacuum manipulation.

Contribution

It introduces a microscopic theory for space-time modulated systems, including moving mirrors and atomic arrays, to produce and control entangled photon pairs via the dynamical Casimir effect.

Findings

Generation of steered frequency-path entangled photon pairs

Production of vortex photon pairs with angular momentum entanglement

Spatio-temporal modulation induces quantum vacuum asymmetry

Abstract

Temporal modulation of the quantum vacuum through fast motion of a neutral body or fast changes of its optical properties is known to promote virtual into real photons, the so-called dynamical Casimir effect. Empowering modulation protocols with spatial control could enable to shape the spectral, spatial, spin, and entanglement properties of the emitted photon pairs. Space-time quantum metasurfaces have been proposed as a platform to realize this physics via modulation of their optical properties. Here, we report the mechanical analog of this phenomenon by considering systems whose lattice structure undergoes modulation in space and in time. We develop a microscopic theory that applies both to moving mirrors with modulated surface profile and atomic array meta-mirrors with perturbed lattice configuration. Spatio-temporal modulation enables motion-induced generation of steered frequency-path entangled photon pairs in co- and cross-polarized states, as well as vortex photon pairs featuring frequency-angular momentum entanglement. The proposed space-time dynamical Casimir effect can be interpreted as an induced dynamical asymmetry in the quantum vacuum.