Cross-over from weak localization to anti-localization in rare doped TRS protected topological insulators

Authors

Zengji Yue, University of WollongongFollow
Weiyao Zhao, University of WollongongFollow
Kirrily C. Rule, University of WollongongFollow
Abuduliken Bake, University of WollongongFollow
Lina Sang, University of WollongongFollow
Guangsai Yang, University of WollongongFollow
Cheng Tan, University of Wollongong
Zhi Li, University of WollongongFollow
Lan Wang, University of Wollongong
Xiaolin Wang, University of WollongongFollow

RIS ID

146061

Publication Details

Yue, Z., Zhao, W., Rule, K., Bake, A., Sang, L., Yang, G., Tan, C., Li, Z., Wang, L. & Wang, X. (2021). Cross-over from weak localization to anti-localization in rare doped TRS protected topological insulators. Physics Letters, Section A: General, Atomic and Solid State Physics, 385

Abstract

© 2020 Elsevier B.V. We study magneto-transport phenomena in two rare-earth doped topological insulators, SmxFexSb2-2xTe3 and SmxBi2-xTe2Se single crystals. The magneto-transport behaviours in both compounds exhibit a novel crossover between weak anti-localization (positive magnetoresistance) and weak localization (negative magnetoresistance) with changes in temperatures and magnetic fields. The weak localization is caused by rare-earth-doping induced magnetization, and the weak anti-localization originates from topologically protected surface states. The transition from weak localization to weak anti-localization demonstrates a gap opening at the Dirac point of the surface states in the quantum diffusive regime. This work demonstrates an effective way to manipulate the magneto-transport properties of the topological insulators by rare-earth element doping. Magnetometry measurements indicate that the Sm-dopant alone is paramagnetic, whereas the co-doped Fe-Sm state has short-range antiferromagnetic order. Our results demonstrate the potential to realize exotic topological effects and magneto-electric effects in gapped surface states of rare earth doped topological insulators.