Topological Surface State Annihilation and Creation in SnTe/Crx(BiSb)2- xTe3 Heterostructures

Peng Deng; Alexander Grutter; Yulei Han; Megan E Holtz; Peng Zhang; Patrick Quarterman; Shuaihang Pan; Shifei Qi; Zhenhua Qiao; Kang L Wang

doi:10.1021/acs.nanolett.2c00774

Topological Surface State Annihilation and Creation in SnTe/Cr_x(BiSb)_{2- x}Te₃ Heterostructures

Nano Lett. 2022 Jul 27;22(14):5735-5741. doi: 10.1021/acs.nanolett.2c00774. Epub 2022 Jul 19.

Authors

Peng Deng^{1

2}, Alexander Grutter³, Yulei Han⁴, Megan E Holtz⁵, Peng Zhang¹, Patrick Quarterman³, Shuaihang Pan⁶, Shifei Qi^{4

7}, Zhenhua Qiao³, Kang L Wang^{1

8}

Affiliations

¹ Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States.
² Beijing Academy of Quantum Information Science, Beijing 100193, China.
³ NIST Center for Neutron Research, National Institute of Standards and Technology, Maryland 20899-6102, United States.
⁴ ICQD, Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, and Department of Physics, University of Science and Technology of China, Anhui 230026, China.
⁵ Materials Measurement Laboratory, National Institute of Standards and Technology, Maryland 20899-6102, United States.
⁶ Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, California 90095, United States.
⁷ College of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Hebei 050024, China.
⁸ Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States.

PMID: 35850534
DOI: 10.1021/acs.nanolett.2c00774

Abstract

Topological surface states are a new class of electronic states with novel properties, including the potential for annihilation between surface states from two topological insulators at a common interface. Here, we report the annihilation and creation of topological surface states in the SnTe/Cr_x(BiSb)_2-xTe₃ (CBST) heterostructures as evidenced by magneto-transport, polarized neutron reflectometry, and first-principles calculations. Our results show that topological surface states are induced in the otherwise topologically trivial two-quintuple-layers thick CBST when interfaced with SnTe, as a result of the surface state annihilation at the SnTe/CBST interface. Moreover, we unveiled systematic changes in the transport behaviors of the heterostructures with respect to changing Fermi level and thickness. Our observation of surface state creation and annihilation demonstrates a promising way of designing and engineering topological surface states for dissipationless electronics.

Keywords: anomalous Hall effect; magnetic topological insulators; polarized neutron reflectometry; surface state annihilation; topological crystalline insulators.