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Title: Probing the low-temperature limit of the quantum anomalous Hall effect
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) 2 Te 3 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.
Authors:
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Award ID(s):
1807817
Publication Date:
NSF-PAR ID:
10227403
Journal Name:
Science Advances
Volume:
6
Issue:
25
Page Range or eLocation-ID:
eaaz3595
ISSN:
2375-2548
Sponsoring Org:
National Science Foundation
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