arXiv:2605.30978

Parity-induced generalized Brillouin zone without non-Hermitian skin effect

Alexander Felski

cond-mat.mes-hallquant-phSubmitted May 29, 2026• Announced Jun 1, 2026

Abstract

Acute spectral sensitivity to boundary conditions and the formation of a generalized Brillouin zone associated with complex quasimomenta are features frequently attributed to systems with non-trivial non-Hermitian topology, showcasing the non-Hermitian skin effect. We show that, away from the thermodynamic limit, these features themselves are not uniquely tied to this phenomenon; they can similarly arise as parity-induced even-odd effects in non-Hermitian systems without skin effect. Despite an underlying generalized Brillouin zone description, wavefunctions remain delocalized. In addition, the effect can arise in skin-effect models as entirely separate distinguishable feature

Comments: article: 5 pages, 4 figures; supplemental: 5 pages, 4 figures

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