A quantized anomalous Hall effect above 4.2 K in stacked topological insulator/magnet bilayers

Rakshit Jain; Matthew Roddy; Vishakha Gupta; Benjamin Huang; Hasan M. Sayeed; Husain F. Alnaser; Amit Vashist; Kenji Watanabe; Takashi Taniguchi; Vikram V. Deshpande; Taylor D. Sparks; Daniel C. Ralph

arXiv · 2412.05380

A quantized anomalous Hall effect above 4.2 K in stacked topological insulator/magnet bilayers

Rakshit Jain·Matthew Roddy·Vishakha Gupta·Benjamin Huang·Hasan M. Sayeed·Husain F. Alnaser·Amit Vashist·Kenji Watanabe·Takashi Taniguchi·Vikram V. Deshpande·Taylor D. Sparks·Daniel C. Ralph

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Abstract

Quantized anomalous Hall effects (QAHEs) occur in remarkable electronic states which possess not only quantized Hall signals but in some cases regions of dissipationless electron transport. The initial demonstrations of a QAHE in a magnetically-doped topological insulator (TI) required temperatures below 100 mK, and since then a major focus of the field has been to increase the temperature scale. Here, we report quantized Hall signals up to 10 K (in what is known as the parity anomaly state) in TI/magnet bilayers made by mechanical assembly, rather than by conventional deposition techniques. This is a factor of 100 higher temperature than any previous realization of a QAHE in a proximity-coupled TI/magnet heterostructure made by deposition, and approximately twice the previous record for any QAHE system.

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Rakshit Jain, Matthew Roddy, Vishakha Gupta, Benjamin Huang, Hasan M. Sayeed, Husain F. Alnaser, Amit Vashist, Kenji Watanabe, Takashi Taniguchi, Vikram V. Deshpande, Taylor D. Sparks, Daniel C. Ralph. 2024-12-06. A quantized anomalous Hall effect above 4.2 K in stacked topological insulator/magnet bilayers. https://arxiv.org/abs/2412.05380

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