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Probing the low-temperature limit of the quantum anomalous Hall effect.

ABSTRACT: Quantum anomalous Hall effect has been observed in magnetically doped topological insulators. However, full quantization, up until now, is limited within the sub-1 K temperature regime, although the material's magnetic ordering temperature can go beyond 100 K. Here, we study the temperature limiting factors of the effect in Cr-doped (BiSb)₂Te₃ systems using both transport and magneto-optical methods. By deliberate control of the thin-film thickness and doping profile, we revealed that the low occurring temperature of quantum anomalous Hall effect in current material system is a combined result of weak ferromagnetism and trivial band involvement. Our findings may provide important insights into the search for high-temperature quantum anomalous Hall insulator and other topologically related phenomena.

SUBMITTER: Pan L

PROVIDER: S-EPMC7299611 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Probing the low-temperature limit of the quantum anomalous Hall effect.

Pan Lei L Liu Xiaoyang X He Qing Lin QL Stern Alexander A Yin Gen G Che Xiaoyu X Shao Qiming Q Zhang Peng P Deng Peng P Yang Chao-Yao CY Casas Brian B Choi Eun Sang ES Xia Jing J Kou Xufeng X Wang Kang L KL

Science advances 20200617 25

Quantum anomalous Hall effect has been observed in magnetically doped topological insulators. However, full quantization, up until now, is limited within the sub-1 K temperature regime, although the material's magnetic ordering temperature can go beyond 100 K. Here, we study the temperature limiting factors of the effect in Cr-doped (BiSb)<sub>2</sub>Te<sub>3</sub> systems using both transport and magneto-optical methods. By deliberate control of the thin-film thickness and doping profile, we re ...[more]

PMID: 32596443

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