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arXiv · 2307.09062

Antiferromagnetic topological insulating state in Tb$_{0.02}$Bi$_{1.08}$Sb$_{0.9}$Te$_2$S single crystals

Lei Guo·Weiyao Zhao·Qile Li·Meng Xu·Lei Chen·Abdulhakim Bake·Thi-Hai-Yen Vu·Yahua He·Yong Fang·David Cortie·Sung-Kwan Mo·Mark Edmonds·Xiaolin Wang·Shuai Dong·Julie Karel·Ren-Kui Zheng
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Abstract

Topological insulators are emerging materials with insulating bulk and symmetry protected nontrivial surface states. One of the most fascinating transport behaviors in a topological insulator is the quantized anomalous Hall insulator, which has been observed inmagnetic-topological-insulator-based devices. In this work, we report a successful doping of rare earth element Tb into Bi$_{1.08}$Sb$_{0.9}$Te$_2$S topological insulator single crystals, in which the Tb moments are antiferromagnetically ordered below ~10 K. Benefiting from the in-bulk-gap Fermi level, transport behavior dominant by the topological surface states is observed below ~ 150 K. At low temperatures, strong Shubnikov-de Haas oscillations are observed, which exhibit 2D-like behavior. The topological insulator with long range magnetic ordering in rare earth doped Bi$_{1.08}$Sb$_{0.9}$Te$_2$S single crystal provides an ideal platform for quantum transport studies and potential applications.

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Lei Guo, Weiyao Zhao, Qile Li, Meng Xu, Lei Chen, Abdulhakim Bake, Thi-Hai-Yen Vu, Yahua He, Yong Fang, David Cortie, Sung-Kwan Mo, Mark Edmonds, Xiaolin Wang, Shuai Dong, Julie Karel, Ren-Kui Zheng. 2023-07-18. Antiferromagnetic topological insulating state in Tb$_{0.02}$Bi$_{1.08}$Sb$_{0.9}$Te$_2$S single crystals. https://doi.org/10.1103/physrevb.107.125125

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