Synthetic magnetism for photon fluids

TL;DR

This paper develops a theory of artificial gauge fields in photon fluids with nonlinearities, revealing how weak excitations experience synthetic magnetic fields influenced by PT-symmetry, with observable consequences demonstrated.

Contribution

It introduces a generalized Bogoliubov theory for photon fluids with second- and third-order nonlinearities, incorporating PT-symmetry effects into artificial gauge fields.

Findings

Artificial gauge fields depend on pump orbital angular momentum.

Synthetic magnetic fields influence weak excitations.

Observable effects demonstrated in nonlinear photon fluids.

Abstract

We develop a theory of artificial gauge fields in photon fluids for the cases of both second-order and third-order optical nonlinearities. This applies to weak excitations in the presence of pump fields carrying orbital angular momentum, and is thus a type of Bogoliubov theory. The resulting artificial gauge fields experienced by the weak excitations are an interesting generalization of previous cases and reflect the PT-symmetry properties of the underlying non-Hermitian Hamiltonian. We illustrate the observable consequences of the resulting synthetic magnetic fields for examples involving both second-order and third-order nonlinearities.