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arXiv · 2406.14465

AC conductivity and magnetic dichroism of two-dimensional antiferromagnetic Dirac semimetals

Reza Sepehrinia·Siavash Eskandari·Alireza Qaiumzadeh
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Abstract

We investigate the magneto-optical properties of two-dimensional nonsymmorphic Dirac semimetals in the presence of antiferromagnetic order. Using the Kubo formula, we calculate the conductivity tensor of two-dimensional CuMnAs, a prototype antiferromagnetic Dirac material, as a function of light frequency. From the finite-frequency conductivity tensor, we derive the dynamic dielectric function and magnetic linear dichroism, demonstrating how they are influenced by the orientation of the N{\'e}el order parameter. Adjusting the N{\'e}el vector changes both the sign and amplitude of the system's magneto-optical response. We propose that magnetic linear dichroism spectroscopy is a powerful technique for determining the orientation of the N{\'e}el vector.

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Reza Sepehrinia, Siavash Eskandari, Alireza Qaiumzadeh. 2024-06-20. AC conductivity and magnetic dichroism of two-dimensional antiferromagnetic Dirac semimetals. https://doi.org/10.1103/physrevb.110.014440

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