Synthetic gauge potential and effective magnetic field in a Raman medium undergoing molecular modulation

TL;DR

This paper theoretically explores how a Raman medium with molecular modulation can generate synthetic gauge potentials and magnetic fields, leading to topologically protected photonic states and suppression of diffraction.

Contribution

It introduces a novel method to induce topological effects in photonics using molecular modulation and synthetic dimensions in a Raman medium.

Findings

Demonstration of effective gauge potential and magnetic field in a Raman medium

Prediction of topologically protected one-way edge states in synthetic space

Observation of Landau levels leading to suppression of diffraction

Abstract

We theoretically demonstrate non-trivial topological effects for a probe field in a Raman medium undergoing molecular modulation processes. The medium is driven by two non-collinear pump beams. We show that the angle between the pumps is related to an effective gauge potential and an effective magnetic field for the probe field in the synthetic space consisting of a synthetic frequency dimension and a spatial dimension. As a result of such effective magnetic field, the probe field can exhibit topologically-protected one-way edge state in the synthetic space, as well as Landau levels which manifests as suppression of both diffraction and sideband generation. Our work identifies a previously unexplored route towards creating topological photonics effects, and highlights an important connection between topological photonics and nonlinear optics.