Unexpected Tuning of the Anomalous Hall Effect in Altermagnetic MnTe Thin Films

Sara Bey; Shelby S. Fields; Nicholas G. Combs; Bence G. Márkus; Dávid Beke; Jiashu Wang; Anton V. Ievlev; Maksym Zhukovskyi; Tatyana Orlova; László Forró; Steven P. Bennett; Xinyu Liu; Badih A. Assaf

arXiv · 2409.04567

Unexpected Tuning of the Anomalous Hall Effect in Altermagnetic MnTe Thin Films

Sara Bey·Shelby S. Fields·Nicholas G. Combs·Bence G. Márkus·Dávid Beke·Jiashu Wang·Anton V. Ievlev·Maksym Zhukovskyi·Tatyana Orlova·László Forró·Steven P. Bennett·Xinyu Liu·Badih A. Assaf

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Abstract

The discovery of an anomalous Hall effect (AHE) sensitive to the magnetic state of antiferromagnets can trigger a new era of spintronics, if materials that host a tunable and strong AHE are identified. Altermagnets are a new class of materials that can under certain conditions manifest a strong AHE, without having a net magnetization. But the ability to control their AHE is still lacking. In this study, we demonstrate that the AHE in altermagnetic {\alpha}-MnTe grown on GaAs(111) substrates can be "written on-demand" by cooling the material under an in-plane magnetic field. The magnetic field controls the strength and the coercivity of the AHE. Remarkably, this control is unique to {\alpha}-MnTe grown on GaAs and is absent in {\alpha}-MnTe grown on SrF2. The tunability that we reveal challenges our current understanding of the symmetry-allowed AHE in this material and opens new possibilities for the design of altermagnetic spintronic devices.

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Sara Bey, Shelby S. Fields, Nicholas G. Combs, Bence G. Márkus, Dávid Beke, Jiashu Wang, Anton V. Ievlev, Maksym Zhukovskyi, Tatyana Orlova, László Forró, Steven P. Bennett, Xinyu Liu, Badih A. Assaf. 2024-09-06. Unexpected Tuning of the Anomalous Hall Effect in Altermagnetic MnTe Thin Films. https://arxiv.org/abs/2409.04567

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