Eur. Phys. J. D (2014) 68: 134
https://doi.org/10.1140/epjd/e2014-40803-6

Regular Article

Perturbative photon production in a dispersive medium

¹ Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo 32, 20133 Milano, Italy
² Dipartimento di Scienza e Alta Tecnologia, Università dell’Insubria, Via Valleggio 11, 22100 Como, Italy
³ INFN sezione di Milano, via Celoria 16, 20133 Milano, Italy
⁴ Università “La Sapienza”, Dipartimento di Matematica, Piazzale A. Moro 2, 00185 Roma, Italy

^a e-mail: f.dallapiazza@gmail.com

Received: 16 December 2013
Received in final form: 11 February 2014
Published online: 28 May 2014

Abstract

We investigate photon pair-creation in a dispersive dielectric medium induced by the presence of a spacetime varying dielectric constant. Our aim is to examine the possibility to observe new phenomena of pair creation induced by travelling dielectric perturbations e.g. created by laser pulses by means of the Kerr effect. In this perspective, we adopt a semi-phenomenological version of the Hopfield model in which a space-time dependent dielectric susceptibility appears. We focus our attention on perturbation theory, and provide general formulas for the photon production induced by a local but arbitrarily spacetime dependent refractive index perturbation. As an example, we further explore the case of a uniformly travelling perturbation, and provide examples of purely time-dependent perturbations.