Premium
Enhancing the Quantum Anomalous Hall Effect by Magnetic Codoping in a Topological Insulator
Author(s) -
Ou Yunbo,
Liu Chang,
Jiang Gaoyuan,
Feng Yang,
Zhao Dongyang,
Wu Weixiong,
Wang XiaoXiao,
Li Wei,
Song Canli,
Wang LiLi,
Wang Wenbo,
Wu Weida,
Wang Yayu,
He Ke,
Ma XuCun,
Xue QiKun
Publication year - 2018
Publication title -
advanced materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.707
H-Index - 527
eISSN - 1521-4095
pISSN - 0935-9648
DOI - 10.1002/adma.201703062
Subject(s) - topological insulator , quantum anomalous hall effect , condensed matter physics , materials science , ferromagnetism , doping , magnetic field , quantum hall effect , quantum , physics , quantum mechanics
The quantum anomalous Hall (QAH) effect, which has been realized in magnetic topological insulators (TIs), is the key to applications of dissipationless quantum Hall edge states in electronic devices. However, investigations and utilizations of the QAH effect are limited by the ultralow temperatures needed to reach full quantization—usually below 100 mK in either Cr‐ or V‐doped (Bi,Sb) 2 Te 3 of the two experimentally confirmed QAH materials. Here it is shown that by codoping Cr and V magnetic elements in (Bi,Sb) 2 Te 3 TI, the temperature of the QAH effect can be significantly increased such that full quantization is achieved at 300 mK, and zero‐field Hall resistance of 0.97 h / e 2 is observed at 1.5 K. A systematic transport study of the codoped (Bi,Sb) 2 Te 3 films with varied Cr/V ratios reveals that magnetic codoping improves the homogeneity of ferromagnetism and modulates the surface band structure. This work demonstrates magnetic codoping to be an effective strategy for achieving high‐temperature QAH effect in TIs.