Quantum Oscillations and Hall Anomaly of Surface States in the Topological Insulator Bi2Te3
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.
D. Qu et al., "Quantum Oscillations and Hall Anomaly of Surface States in the Topological Insulator Bi2Te3," Science, vol. 329, no. 5993, pp. 821-824, American Association for the Advancement of Science (AAAS), Aug 2010.
The definitive version is available at http://dx.doi.org/10.1126/science.1189792
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)
Article - Journal
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