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arXiv · 1111.5800

Mechanisms of enhanced orbital dia- and paramagnetism: Application to the Rashba semiconductor BiTeI

G. A. H. Schober·H. Murakawa·M. S. Bahramy·R. Arita·Y. Kaneko·Y. Tokura·N. Nagaosa
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Abstract

We study the magnetic susceptibility of a layered semiconductor BiTeI with giant Rashba spin splitting both theoretically and experimentally to explore its orbital magnetism. Apart from the core contributions, a large temperature-dependent diamagnetic susceptibility is observed when the Fermi energy E_F is near the crossing point of the conduction bands, while the susceptibility turns to be paramagnetic when E_F is away from it. These features are consistent with first-principles calculations, which also predict an enhanced orbital magnetic susceptibility with both positive and negative signs as a function of E_F due to band (anti)crossings. Based on these observations, we propose two mechanisms for an enhanced paramagnetic orbital susceptibility.

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G. A. H. Schober, H. Murakawa, M. S. Bahramy, R. Arita, Y. Kaneko, Y. Tokura, N. Nagaosa. 2011-11-24. Mechanisms of enhanced orbital dia- and paramagnetism: Application to the Rashba semiconductor BiTeI. https://doi.org/10.1103/physrevlett.108.247208

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