Propagation of a quantum fluid of light in a cavityless nonlinear optical medium: General theory and response to quantum quenches

TL;DR

This paper develops a generalized quantum theory for light propagation in nonlinear media, exploring how photon fluids respond to quantum quenches and predicting unique statistical properties of the emitted light.

Contribution

It introduces a novel theoretical framework for cavityless photon fluids and analyzes their response to quantum quenches, extending Bogoliubov theory to this context.

Findings

Predicted unique statistical features of light after quantum quenches.

Extended Bogoliubov theory to photon fluids in nonlinear media.

Analyzed the response of photon fluids to interaction changes at medium boundaries.

Abstract

Making use of a generalized quantum theory of paraxial light propagation where the radiation-axis and the temporal coordinates play exchanged roles, we discuss the potential of bulk nonlinear optical media in cavityless configurations for quantum statistical mechanics studies of the conservative many-body dynamics of a gas of interacting photons. To illustrate the general features of this point of view, we investigate the response of the fluid of light to the quantum quenches in the photon-photon interaction constant experienced at the front and the back faces of a finite slab of weakly nonlinear material. Extending the standard Bogoliubov theory of dilute Bose-Einstein condensates, peculiar features are predicted for the statistical properties of the light emerging from the nonlinear medium.