Polariton condensation into vortex states in the synthetic magnetic field of a strained honeycomb lattice

TL;DR

This paper demonstrates how a strained honeycomb lattice of resonators can induce a synthetic magnetic field, enabling polariton condensation into vortex states, thus mimicking magnetic effects in light without external magnetic fields.

Contribution

It introduces a novel method to create a synthetic magnetic field in photonic systems using strain, leading to vortex formation in polariton condensates without external rotation.

Findings

Polariton condensates occupy the lowest Landau level in the synthetic magnetic field.

Vortex arrays spontaneously form in the condensate due to competition between interactions and dissipation.

The system provides a platform to study vortex physics and quantum Hall analogues with light.

Abstract

Photonic materials are a rapidly growing platform for studying condensed matter physics with light, where the exquisite control capability is allowing us to learn about the relation between microscopic dynamics and macroscopic properties. One of the most interesting aspects of condensed matter is the interplay between interactions and the effect of an external magnetic field or rotation, responsible for a plethora of rich phenomena -- Hall physics and quantized vortex arrays. At first sight, however, these effects for photons seem vetoed: they do not interact with each other and they are immune to magnetic fields and rotations. Yet in specially devised structures these effects can be engineered. Here, we propose the use of a synthetic magnetic field induced by strain in a honeycomb lattice of resonators to create a non-equilibrium Bose-Einstein condensate of light-matter particles (polaritons) in a rotating state, without the actual need for external rotation nor reciprocity-breaking elements. We show that thanks to the competition between interactions, dissipation and a suitably designed incoherent pump, the condensate spontaneously becomes chiral by selecting a single Dirac valley of the honeycomb lattice, occupying the lowest Landau level and forming a vortex array. Our results offer a new platform where to study the exciting physics of arrays of quantized vortices with light and pave the way to explore the transition from a vortex-dominated phase to the photonic analogue of the fractional quantum Hall regime.