Related papers: Topological Protection in non-Hermitian Haldane Honeycomb Lattices

Topological Protection in non-Hermitian Haldane Honeycomb Lattices

URL: http://arxiv.org/abs/2003.14375v1
Date: Tue, 31 Mar 2020 17:14:51 GMT
Title: Topological Protection in non-Hermitian Haldane Honeycomb Lattices
Authors: Pablo Res\'endiz-V\'azquez, Konrad Tschernig, Armando Perez-Leija, Kurt Busch, Roberto de J. Le\'on-Montiel
Abstract summary: Topological phenomena in non-Hermitian systems have recently become a subject of great interest in the photonics and condensed-matter communities. We present the first study on the emergence of topological edge states in two-dimensional Haldane lattices exhibiting balanced gain and loss.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: Topological phenomena in non-Hermitian systems have recently become a subject of great interest in the photonics and condensed-matter communities. In particular, the possibility of observing topologically-protected edge states in non-Hermitian lattices has sparked an intensive search for systems where this kind of states are sustained. Here, we present the first study on the emergence of topological edge states in two-dimensional Haldane lattices exhibiting balanced gain and loss. In line with recent studies on other Chern insulator models, we show that edge states can be observed in the so-called broken $\mathcal{P}\mathcal{T}$-symmetric phase, that is, when the spectrum of the gain-loss-balanced system's Hamiltonian is not entirely real. More importantly, we find that such topologically protected edge states emerge irrespective of the lattice boundaries, namely zigzag, bearded or armchair.

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