Spectral localizer for line-gapped non-Hermitian systems
نویسندگان
چکیده
Short-ranged and line-gapped non-Hermitian Hamiltonians have strong topological invariants given by an index of associated Fredholm operator. It is shown how these can be accessed via the signature a suitable spectral localizer. This numerical technique implemented in example with relevance to design photonic systems, such as lasers.
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ژورنال
عنوان ژورنال: Journal of Mathematical Physics
سال: 2023
ISSN: ['0022-2488', '1527-2427', '1089-7658']
DOI: https://doi.org/10.1063/5.0150995