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Updated: Jun 10, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Quantum oscillations and hall anomaly of surface states in the topological insulator Bi2Te3
Dong-Xia Qu1, Y S Hor, Jun Xiong
1Department of Physics, Princeton University, Princeton, NJ 08544, USA. dqu@princeton.edu
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 Bi(2)Te(3). 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 centimeter(2) 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.
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