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arXiv · 2607.05470

Non-Hermitian Tight-Binding Bands in Graphene: Optical Conductivity, Strain Effects, and Bernal Bilayer Extension

Maolin Bo·Yaorui Tan·Sunxin Fan·Xiang Chen·Yunhu Zhu·Zhongkai Huang·Chuang Yao
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Abstract

Within the tight binding framework of graphenes {\pi} electron nearest neighbors, the Tan Bo model parametrizes transition energies t(dr) based on bond lengths and angles via the Mobius transformation combined with exponential decay. Comparisons between isotropic , geometrically anisotropic , and Slater Koster scales reveal that B = 0 is equivalent to the SK scheme, with L(B) reaching its optimum at Bopt = 0. The Hermitian assembly maintains the Dirac cone at the K point.The Tan Bo geometry dependent transition model and non Hermitian TB assembly scheme developed in this study provide a reproducible single particle benchmark and parameterization reference for future non Hermitian chemical calculations incorporating electron correlation effects in graphene systems.

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Maolin Bo, Yaorui Tan, Sunxin Fan, Xiang Chen, Yunhu Zhu, Zhongkai Huang, Chuang Yao. 2026-07-06. Non-Hermitian Tight-Binding Bands in Graphene: Optical Conductivity, Strain Effects, and Bernal Bilayer Extension. https://arxiv.org/abs/2607.05470

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