Quantum Oscillations and Hall Anomaly of Surface States in the Topological Insulator Bi₂Te₃

Abstract

Topological insulators are insulating materials that display massless, Dirac-like surface states in which the electrons have only one spin degree of freedom on each surface. These states have been imaged by photoemission, but little information on their transport parameters, for example, mobility, is available. We report the observation of Shubnikov - de Haas oscillations arising from the surface states in nonmetallic crystals of Bi2Te3. In addition, we uncovered a Hall anomaly in weak fields, which enables the surface current to be seen directly. Both experiments yield a surface mobility (9000 to 10,000 centimeter2 per volt-second) that is substantially higher than in the bulk. The Fermi velocity of 4 x 10 5 meters per second obtained from these transport experiments agrees with angle-resolved photoemission experiments.

Department(s)

Physics

Keywords and Phrases

Bismuth Derivative; Bismuth Telluride; Nonmetal; Tellurium Derivative; Unclassified Drug; Crystal; Electron; Insulation; Parameterization; Quantum Mechanics; Topology; Velocity; Conductor; Controlled Study; Electric Field; Electric Potential; Oscillation; Quantum Oscillation; Quantum Yield; Surface Property; Thermal Conductivity; Topological Insulator; Velocity

International Standard Serial Number (ISSN)

0036-8075

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2010 American Association for the Advancement of Science (AAAS), All rights reserved.

Publication Date

01 Aug 2010

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