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arXiv · 2601.00487

Non-Hermitian Band Topology and Edge States in Atomic Lattices

Wenxuan Xie·John C Schotland
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Abstract

We investigate the band structure and topological phases of one- and two-dimensional bipartite atomic lattices mediated by long-range dissipative radiative coupling. By deriving an effective non-Hermitian Hamiltonian for the single-excitation sector, we demonstrate that the low-energy dynamics of the system are governed by a Dirac equation with a complex Fermi velocity. We analyze the associated topological invariants for both the SSH and honeycomb models, utilizing synthetic gauge fields to break time-reversal symmetry in the latter. Finally, we explicitly verify the non-Hermitian bulk-edge correspondence by deriving analytical solutions for edge states localized at domain boundaries.

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Wenxuan Xie, John C Schotland. 2026-01-01. Non-Hermitian Band Topology and Edge States in Atomic Lattices. https://arxiv.org/abs/2601.00487

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