Dymamical Casimir emission from polariton condensates

TL;DR

This paper theoretically investigates the dynamical Casimir effect in exciton-polariton condensates created by ultrashort laser pulses, analyzing the resulting excitations, coherence, and depletion.

Contribution

It introduces a linearized Wigner approximation to study the evolution of polariton condensates post-creation, revealing analytical behaviors and scaling relations.

Findings

Analytical expressions for momentum distribution at large and small momenta.

A scaling relation for condensate depletion based on system parameters.

Correlation length depends linearly on condensate depletion.

Abstract

We study theoretically the dynamical Casimir effect in an exciton-polariton condensate that is suddenly created by an ultrashort laser pulse at normal incidence. As a consequence of the abrupt change of the quantum vacuum, Bogoliubov excitations are generated. The subsequent evolution, governed by polariton interactions and losses, is studied within a linearized truncted Wigner approximation. We focus in particular on the momentum distribution and spatial coherence. The limiting behavior at large and small momenta is determined analytically. A simple scaling relation for the final condensate depletion as a function of the system parameters is found and the correlation length is shown to depend linearly on the condensate depletion.