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arXiv · 2312.03094

Magneto-optical response of the Weyl semimetal NbAs: Experimental results and hyperbolic-band computations

S. Polatkan·E. Uykur·J. Wyzula·M. Orlita·C. Shekhar·C. Felser·M. Dressel·A. V. Pronin
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Abstract

The magneto-optical properties of (001)-oriented NbAs single crystals have been studied in the spectral range from 5 to 150 meV and in magnetic fields of up to 13 T. A rich spectrum of inter-Landau-level transitions is revealed by these measurements. The transitions follow a square-root-like dependence with magnetic field, but the simple linear-band approximation is unable to accurately reproduce the observed behavior of the transitions in applied fields. We argue that the detected magneto-optical spectra should be related to crossing hyperbolic bands, which form the W1 cones. We propose a model Hamiltonian, which describes coupled hyperbolic bands and reproduces the shape of the relevant bands in NbAs. The magneto-optical spectra computed from this Hamiltonian nicely reproduce our observations. We conclude that the hyperbolic-band approach is a minimal model to adequately describe the magneto-optical response of NbAs and that the chiral (conical) bands do not explicitly manifest themselves in the spectra.

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S. Polatkan, E. Uykur, J. Wyzula, M. Orlita, C. Shekhar, C. Felser, M. Dressel, A. V. Pronin. 2023-12-05. Magneto-optical response of the Weyl semimetal NbAs: Experimental results and hyperbolic-band computations. https://doi.org/10.1103/physrevb.108.l241201

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