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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.  more » « less
Award ID(s):
1807817
PAR ID:
10227403
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
25
ISSN:
2375-2548
Page Range / eLocation ID:
eaaz3595
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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