Year: 2025
Type: article
Abstract: This article presents an examination of a two-dimensional, non-Hermitian Su–Schrieffer–Heeger model, which differs 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 enables identification of true exceptional points. Furthermore, this investigation achieves vectorized Zak phase quantization and examines a topolectric resistors–inductors–capacitors 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.
Source: Acta Physica Polonica A
Authors: U.P. Tyagi, P. Goswami
Institution: University of Delhi
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4413308008