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arXiv · 2406.07626

Tailoring Bound State Geometry in High-Dimensional Non-Hermitian Systems

Ao Yang·Zixi Fang·Kai Zhang·Chen Fang
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Abstract

It is generally believed that the non-Hermitian effect (NHSE), due to its non-reciprocal nature, creates barriers for the appearance of impurity bound states. In this paper, we find that in two and higher dimensions, the presence of geometry-dependent skin effect eliminates this barrier such that even an infinitesimal impurity potential can confine bound states in this type of non-Hermitian systems. By examining bound states around Bloch saddle points, we find that non-Hermiticity can disrupt the isotropy of bound states, resulting in concave dumbbell-shaped bound states. Our work reveals a geometry transition of bound state between concavity and convexity in high-dimensional non-Hermitian systems, offering theoretical insights for the experimental manipulation of bound states.

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Ao Yang, Zixi Fang, Kai Zhang, Chen Fang. 2024-06-11. Tailoring Bound State Geometry in High-Dimensional Non-Hermitian Systems. https://doi.org/10.1038/s42005-025-02037-w

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