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arXiv · 2003.01539

First Principles Calculation of Topological Invariants of non-Hermitian Photonic Crystals

Filipa R. Prudêncio·Mário G. Silveirinha
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Abstract

The Chern topological numbers of a material platform are usually written in terms of the Berry curvature, which depends on the normal modes of the system. Here, we use a gauge invariant Green's function method to determine from first principles the topological invariants of photonic crystals. The proposed formalism does not require the calculation of the photonic band-structure, and can be easily implemented using the operators obtained with a standard plane-wave expansion. Furthermore, it is shown that the theory can be readily applied to the classification of topological phases of non-Hermitian photonic crystals with lossy or gainy materials, e.g., parity-time symmetric photonic crystals.

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Filipa R. Prudêncio, Mário G. Silveirinha. 2020-03-03. First Principles Calculation of Topological Invariants of non-Hermitian Photonic Crystals. https://arxiv.org/abs/2003.01539

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