Weak Anti-localization and Quantum Oscillations of Surface States in Topological Insulator Bi2Se2Te

Date
2012-10-11
Authors
Lograsso, Thomas
Bao, Lihong
He, Liang
Tuttle, Gary
Meyer, Nicholas
Kou, Xufeng
Zhang, Peng
Chen, Zhi-gang
Fedorov, Alexei
Riedemann, Trevor
Lograsso, Thomas
Wang, Kang
Tuttle, Gary
Xiu, Faxian
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Altmetrics
Authors
Research Projects
Organizational Units
Ames Laboratory
Organizational Unit
Journal Issue
Series
Department
Ames Laboratory
Abstract

Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. Here, we report the observation of weak anti-localization and quantum oscillations originated from surface states in Bi2Se2Te crystals. Angle-resolved photoemission spectroscopy measurements on cleaved Bi2Se2Te crystals show a well-defined linear dispersion without intersection of the conduction band. The measured weak anti-localization effect agrees well with the Hikami-Larkin-Nagaoka model and the extracted phase coherent length shows a power-law dependence with temperature ( ∼T−0.44), indicating the presence of the surface states. More importantly, the analysis of a Landau-level fan diagram of Shubnikov-de Hass oscillations yields a finite Berry phase of ∼0.42π, suggesting the Dirac nature of the surface states. Our results demonstrate that Bi2Se2Te can serve as a suitable topological insulator candidate for achieving intrinsic quantum transport of surface Dirac fermions.

Comments

This article is from Scientific Reports 2 (2012): 726, doi:10.1038/srep00726.

Description
Keywords
Citation
DOI
Collections