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arXiv · 2506.16867

An investigation of the two-dimensional non-Hermitian Su-Schrieffer-Heeger Model

Udai Prakash Tyagi·Partha Goswami
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Abstract

This communication presents an examination of a two-dimensional, non-Hermitian Su -Schrieffer-Heeger (SSH) model, which is differentiated from its conventional Hermitian counterpart by incorporating gain and/or loss terms, mathematically represented by imaginary on-site potentials. The time-reversal symmetry is disrupted due to these on-site potentials. Exceptional points in a non-Hermitian system feature eigenvalue coalescence and non-trivial eigenvector degeneracies. Utilization of the rank-nullity theorem and graphical analysis of the phase rigidity factor enable identification of true exceptional points. Furthermore, this investigation achieves vectorized Zak phase quantization and examines a topolectric RLC circuit to derive the corresponding topological boundary resonance condition and the quantum Hall susceptance. Although Chern number quantization is not feasible, staggered hopping amplitudes corresponding to unit-cell lattice sites lead to broken inversion symmetry with non-zero Berry curvature, resulting in finite anomalous Nernst conductivity.

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Udai Prakash Tyagi, Partha Goswami. 2025-06-20. An investigation of the two-dimensional non-Hermitian Su-Schrieffer-Heeger Model. https://arxiv.org/abs/2506.16867

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