Terahertz Response and Colossal Kerr Rotation from the Surface States of the Topological Insulator Bi2Se3
Terahertz Response and Colossal Kerr Rotation from the Surface States of the Topological Insulator Bi2Se3
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DOI：
10.1103/physrevlett.108.087403
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发表时间：
2012-02-22
影响因子：
8.6
通讯作者：
Armitage, N. P.
中科院分区：
文献类型：
--
作者：
Aguilar, R. Valdes;Stier, A. V.;Armitage, N. P.
本文报道了拓扑绝缘体Bi2Se3薄膜的太赫兹响应。在低频时，输运基本上与厚度无关，显示出表面电子的主要贡献。尽管暴露在环境条件下的时间较长，但这些表面表现出强大的特性，包括窄的、几乎与厚度无关的德鲁德峰，以及在外加磁场中反射的线偏振光的前所未有的大偏振旋转。这种克尔旋转可以大到65度，可以用表面态的回旋共振效应来解释。
We report the THz response of thin films of the topological insulator Bi2Se3. At low frequencies, transport is essentially thickness independent showing the dominant contribution of the surface electrons. Despite their extended exposure to ambient conditions, these surfaces exhibit robust properties including narrow, almost thickness-independent Drude peaks, and an unprecedentedly large polarization rotation of linearly polarized light reflected in an applied magnetic field. This Kerr rotation can be as large as 65 degrees and can be explained by a cyclotron resonance effect of the surface states.