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

• URL: http://arxiv.org/abs/2406.07626v1
• Date: Tue, 11 Jun 2024 18:00:12 GMT
• Title: Tailoring Bound State Geometry in High-Dimensional Non-Hermitian Systems
• Authors: Ao Yang, Zixi Fang, Kai Zhang, Chen Fang,
• Abstract summary: The non-Hermitian effect (NHSE) creates barriers for the appearance of impurity bound states. Our work reveals a geometry transition of bound state between concavity and convexity in high-dimensional non-Hermitian systems.
• Score: 12.085380828370914
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/
• 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.

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