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arXiv · 2205.01622

Magnetic freeze-out and anomalous Hall effect in ZrTe$_5$

Adrien Gourgout·Maxime Leroux·Jean-Loup Smirr·Maxime Massoudzadegan·Ricardo P. S. M. Lobo·David Vignolles·Cyril Proust·Helmuth Berger·Qiang Li·Genga Gu·Christopher C. Homes·Ana Akrap·Benoît Fauqué
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Abstract

The ultra-quantum limit is achieved when a magnetic field confines an electron gas in its lowest spin-polarised Landau level. Here we show that in this limit, electron doped ZrTe$_5$ shows a metal-insulator transition followed by a sign change of the Hall and Seebeck effects at low temperature. We attribute this transition to a magnetic freeze-out of charge carriers on the ionised impurities. The reduction of the charge carrier density gives way to an anomalous Hall response of the spin-polarised electrons. This behaviour, at odds with the usual magnetic freeze-out scenario, occurs in this Dirac metal because of its tiny Fermi energy, extremely narrow band gap and a large $g$-factor. We discuss the different possible sources (intrinsic or extrinsic) for this anomalous Hall contribution.

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Adrien Gourgout, Maxime Leroux, Jean-Loup Smirr, Maxime Massoudzadegan, Ricardo P. S. M. Lobo, David Vignolles, Cyril Proust, Helmuth Berger, Qiang Li, Genga Gu, Christopher C. Homes, Ana Akrap, Benoît Fauqué. 2022-05-03. Magnetic freeze-out and anomalous Hall effect in ZrTe$_5$. https://arxiv.org/abs/2205.01622

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