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arXiv · 1007.4482

Terahertz Kerr and Reflectivity Measurements on the Topological Insulator Bi2Se3

G. S. Jenkins·A. B. Sushkov·D. C. Schmadel·N. P. Butch·P. Syers·J. Paglione·H. D. Drew
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Abstract

We report the first terahertz Kerr measurements on bulk crystals of the topological insulator Bi2Se3. At T=10K and fields up to 8T, the real and imaginary Kerr angle and reflectance measurements utilizing both linearly and circularly polarized incident radiation were measured at a frequency of 5.24meV. A single fluid free carrier bulk response can not describe the line-shape. Surface states with a small mass and surprisingly large associated spectral weight quantitatively fit all data. However, carrier concentration inhomogeneity has not been ruled out. A method employing a gate is shown to be promising for separating surface from bulk effects.

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G. S. Jenkins, A. B. Sushkov, D. C. Schmadel, N. P. Butch, P. Syers, J. Paglione, H. D. Drew. 2010-07-27. Terahertz Kerr and Reflectivity Measurements on the Topological Insulator Bi2Se3. https://doi.org/10.1103/physrevb.82.125120

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