Topological Effects in Two-Dimensional Quantum Emitter Systems

TL;DR

This paper explores how topological properties of two-dimensional bosonic insulators influence quantum emitter behavior, revealing fragile quasibound states, long-range interactions, and topologically non-trivial polariton models.

Contribution

It introduces new effects of topology on emitter dynamics and effective models, including the impact of bath topology on interactions and polariton states.

Findings

Fragile quasibound states in Haldane model

Topology-dependent long-range interactions

Topologically non-trivial polariton models

Abstract

In this work we discuss particular effects that take place in systems of quantum emitters coupled to two-dimensional bosonic topological insulators. For a single emitter coupled to the Haldane model, we find a "fragile" quasibound state that makes the emitter dynamics very sensitive to the model's parameters, and gives rise to effective long-range interactions that break time-reversal symmetry. We then discuss one-dimensional arrangements of emitters, emitter line defects, and how the topology of the bath affects the effective polariton models that appear in the weak-coupling regime when the emitters are spectrally tuned to a bandgap. In the Harper-Hofstadter model we link the non-monotonic character of the effective interactions to the Chern numbers of the surrounding energy bands, while in the Haldane model we show that the effective models are either gapless or not depending on the topology of the bath. Last, we discuss how the presence of emitters forming an ordered array, an emitter superlattice, can produce polariton models with non-trivial Chern numbers, and also modify the topology of the photonic states in the bath.