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arXiv · 1508.04704

Magneto-Infrared Spectroscopic Study of Ultrathin Bi$_{2}$Te$_{3}$ Single Crystals

Abstract

Ultrathin Bi$_{2}$Te$_{3}$ single crystals laid on Scotch tape are investigated by Fourier transform infrared spectroscopy at $4$K and in a magnetic field up to $35$T. The magneto-transmittance spectra of the Bi$_{2}$% Te$_{3}$/tape composite are analyzed as a two-layer system and the optical conductivity of Bi$_{2}$Te$_{3}$ at different magnetic fields are extracted. We find that magnetic field modifies the optical conductivity in the following ways: (1) Field-induced transfer of the optical weight from the lower frequency regime ($<250$cm$^{-1}$) to the higher frequency regime ($% >250$cm$^{-1}$) due to the redistribution of charge carriers across the Fermi surface. (2) Evolving of a Fano-resonance-like spectral feature from an anti-resonance to a resonance with increasing magnetic field. Such behavior can be attributed to the electron-phonon interactions between the $% E_{u}^{1}$ optical phonon mode and the continuum of electronic transitions. (3) Cyclotron resonance resulting from the inter-valence band Landau level transitions, which can be described by the electrodynamics of massive Dirac holes.

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BibTeXRIS

L. -C. Tung, W. Yu, P. Cadden-Zimansky, I. Miotkowski, Y. P. Chen, D. Smirnov, Z. Jiang. 2016-02-02. Magneto-Infrared Spectroscopic Study of Ultrathin Bi$_{2}$Te$_{3}$ Single Crystals. https://doi.org/10.1103/physrevb.93.085140

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