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arXiv · 1910.07571

Magneto-optical probe of the fully gapped Dirac band in ZrSiS

E. Uykur·L. Z. Maulana·L. M. Schoop·B. V. Lotsch·M. Dressel·A. V. Pronin
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Abstract

We present a far-infrared magneto-optical study of the gapped nodal-line semimetal ZrSiS in magnetic fields $B$ up to 7 T. The observed field-dependent features, which represent intra- (cyclotron resonance) and interband transitions, develop as $\sqrt{B}$ in increasing field and can be consistently explained within a simple 2D Dirac band model with a gap of 26 meV and an averaged Fermi velocity of $3\times10^{5}$ m/s. This indicates a rather narrow distribution of these parameters along the in-plane portions of the nodal line in the Brillouin zone. A field-induced feature with an energy position that does not depend on $B$ is also detected in the spectra. Possible origins of this feature are discussed.

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E. Uykur, L. Z. Maulana, L. M. Schoop, B. V. Lotsch, M. Dressel, A. V. Pronin. 2019-10-16. Magneto-optical probe of the fully gapped Dirac band in ZrSiS. https://doi.org/10.1103/physrevresearch.1.032015

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