Chiral Bogoliubons in Nonlinear Bosonic Systems

TL;DR

This paper proposes a method to generate topological chiral Bogoliubov excitations in nonlinear bosonic systems using a Kagome vortex lattice, enabling edge modes without external magnetic fields.

Contribution

It introduces a versatile scheme for creating topological Bogoliubov excitations in 2D nonlinear bosonic systems without external magnetic fields, based on a Kagome vortex lattice.

Findings

Topological gaps with chiral edge modes are demonstrated in the model.

The scheme is applicable to various physical systems like optical and exciton-polariton condensates.

No external magnetic flux is needed for topological protection.

Abstract

We present a versatile scheme for creating topological Bogoliubov excitations in weakly interacting bosonic systems. Our proposal relies on a background stationary field that consists of a Kagome vortex lattice, which breaks time-reversal symmetry and induces a periodic potential for Bogoliubov excitations. In analogy to the Haldane model, no external magnetic field or net flux is required. We construct a generic model based on the two-dimensional (2D) nonlinear Schr\"odinger equation and demonstrate the emergence of topological gaps crossed by chiral Bogoliubov edge modes. Our scheme can be realized in a wide variety of physical systems ranging from nonlinear optical systems to exciton-polariton condensates.