Optical Transmission of 2D Material with Quantum Anomalous Hall Effect

Nathan Pravda; Oleg L. Berman; Klaus Ziegler

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arXiv · 2605.23211

Optical Transmission of 2D Material with Quantum Anomalous Hall Effect

Nathan Pravda·Oleg L. Berman·Klaus Ziegler

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Abstract

We study the optical properties of gapped two-dimensional materials which are subject to the quantum anomalous Hall effect. At sufficiently low temperatures the transmission, reflection and absorption coefficients are found to have a universal behavior that depends only on the ratio of the photonic energy and the gap energy. There is a singular behavior with total reflection when these energies are equal. In the limit of a vanishing gap we recover results for graphene, where the optical coefficients depend only on the fine-structure constant. The observed optical properties provide an accurate measurement of the bandgap.

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Nathan Pravda, Oleg L. Berman, Klaus Ziegler. 2026-05-22. Optical Transmission of 2D Material with Quantum Anomalous Hall Effect. https://arxiv.org/abs/2605.23211

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