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arXiv · 2309.10110

Topological modes and spectral flows in inhomogeneous PT-symmetric continuous media

Yichen Fu·Hong Qin
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Abstract

In classical Hermitian continuous media, the spectral-flow index of topological modes is linked to the bulk topology via index theorem. However, the interface between two bulks is usually non-Hermitian due to the inhomogeneities of system parameters. We show that the connection between topological modes and bulk topology still exists despite the non-Hermiticity at the interface if the system is endowed with PT symmetry. The theoretical framework developed is applied to the Hall magnetohydrodynamic model to identify a topological mode called topological Alfv\'{e}n-sound wave in magnetized plasmas.

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physics.plasm-phcond-mat.mes-hallphysics.flu-dynquant-ph

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BibTeXRIS

Yichen Fu, Hong Qin. 2023-09-18. Topological modes and spectral flows in inhomogeneous PT-symmetric continuous media. https://doi.org/10.1103/physrevresearch.6.023273

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