TY - JOUR
T1 - Magnetic quantum phase transition in Cr-doped Bi2 (Sex Te1-x)3 driven by the Stark effect
AU - Zhang, Zuocheng
AU - Feng, Xiao
AU - Wang, Jing
AU - Lian, Biao
AU - Zhang, Jinsong
AU - Chang, Cuizu
AU - Guo, Minghua
AU - Ou, Yunbo
AU - Feng, Yang
AU - Zhang, Shou Cheng
AU - He, Ke
AU - Ma, Xucun
AU - Xue, Qi Kun
AU - Wang, Yayu
N1 - Funding Information:
The authors thank P. Tang, J. Li and H. Zhang for discussions. This work was supported by the National Natural Science Foundation of China and the Ministry of Science and Technology of China. This work is supported in part by the Beijing Advanced Innovation Center for Future Chip (ICFC). B.L., J.W. and S.-C.Z. acknowledge support from the US Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering (contract no. DE-AC02-76SF00515). J.W. acknowledges support from the National Thousand-Young-Talents Program.
Publisher Copyright:
© 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.
PY - 2017/10/1
Y1 - 2017/10/1
N2 - The recent experimental observation of the quantum anomalous Hall effect has cast significant attention on magnetic topological insulators. In these magnetic counterparts of conventional topological insulators such as Bi 2 Te 3, a long-range ferromagnetic state can be established by chemical doping with transition-metal elements. However, a much richer electronic phase diagram can emerge and, in the specific case of Cr-doped Bi2 (Sex Te1-x)3, a magnetic quantum phase transition tuned by the actual chemical composition has been reported. From an application-oriented perspective, the relevance of these results hinges on the possibility to manipulate magnetism and electronic band topology by external perturbations such as an electric field generated by gate electrodes - similar to what has been achieved in conventional diluted magnetic semiconductors. Here, we investigate the magneto-transport properties of Cr-doped Bi2 (Sex Te1-x)3 with different compositions under the effect of a gate voltage. The electric field has a negligible effect on magnetic order for all investigated compositions, with the remarkable exception of the sample close to the topological quantum critical point, where the gate voltage reversibly drives a ferromagnetic-to-paramagnetic phase transition. Theoretical calculations show that a perpendicular electric field causes a shift in the electronic energy levels due to the Stark effect, which induces a topological quantum phase transition and, in turn, a magnetic phase transition.
AB - The recent experimental observation of the quantum anomalous Hall effect has cast significant attention on magnetic topological insulators. In these magnetic counterparts of conventional topological insulators such as Bi 2 Te 3, a long-range ferromagnetic state can be established by chemical doping with transition-metal elements. However, a much richer electronic phase diagram can emerge and, in the specific case of Cr-doped Bi2 (Sex Te1-x)3, a magnetic quantum phase transition tuned by the actual chemical composition has been reported. From an application-oriented perspective, the relevance of these results hinges on the possibility to manipulate magnetism and electronic band topology by external perturbations such as an electric field generated by gate electrodes - similar to what has been achieved in conventional diluted magnetic semiconductors. Here, we investigate the magneto-transport properties of Cr-doped Bi2 (Sex Te1-x)3 with different compositions under the effect of a gate voltage. The electric field has a negligible effect on magnetic order for all investigated compositions, with the remarkable exception of the sample close to the topological quantum critical point, where the gate voltage reversibly drives a ferromagnetic-to-paramagnetic phase transition. Theoretical calculations show that a perpendicular electric field causes a shift in the electronic energy levels due to the Stark effect, which induces a topological quantum phase transition and, in turn, a magnetic phase transition.
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U2 - 10.1038/nnano.2017.149
DO - 10.1038/nnano.2017.149
M3 - Article
C2 - 28785093
AN - SCOPUS:85030788797
SN - 1748-3387
VL - 12
SP - 953
EP - 957
JO - Nature Nanotechnology
JF - Nature Nanotechnology
IS - 10
ER -