Topological Phase Transition-Induced Triaxial Vector Magnetoresistance in (Bi1–x In x )2Se3 Nanodevices

• Published in: ACS nano Vol. 12; no. 2; pp. 1537 - 1543
• Main Authors: Zhang, Minhao, Wang, Huaiqiang, Mu, Kejun, Wang, Pengdong, Niu, Wei, Zhang, Shuai, Xiao, Guiling, Chen, Yequan, Tong, Tong, Fu, Dongzhi, Wang, Xuefeng, Zhang, Haijun, Song, Fengqi, Miao, Feng, Sun, Zhe, Xia, Zhengcai, Wang, Xinran, Xu, Yongbing, Wang, Baigeng, Xing, Dingyu, Zhang, Rong
• Format: Journal Article
• Language: English
• Published: American Chemical Society 27.02.2018
• Subjects: topological insulators; topological critical point; intersurface coupling; triaxial vector magnetoresistance; topological phase transition
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.7b08054

We report the study of a triaxial vector magnetoresistance (MR) in nonmagnetic (Bi1–x In x )2Se3 nanodevices at the composition of x = 0.08. We show a dumbbell-shaped in-plane negative MR up to room temperature as well as a large out-of-plane positive MR. MR at three directions is about in a −3%:–1%:225% ratio at 2 K. Through both the thickness and composition-dependent magnetotransport measurements, we show that the in-plane negative MR is due to the topological phase transition enhanced intersurface coupling near the topological critical point. Our devices suggest the great potential for room-temperature spintronic applications in, for example, vector magnetic sensors.