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arXiv · 1201.2505

Magnetoexcitons and optical absorption of bilayer-structured topological insulators

Zhigang Wang·Zhen-Guo Fu·Ping Zhang
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Abstract

Optical absorption properties of magnetoexcitons in topological insulator bilayers under a strong magnetic field are theoretically studied. A general analytical formula of optical absorption selection rule is obtained in the noninteracting as well as Coulomb intra-Landau-level interacting cases, which remarkably helps to interpret the resonant peaks in absorption spectroscopy and the corresponding formation of Dirac-type magnetoexcitons. We also discuss the optical absorption spectroscopy of magnetoexcitons in the presence of inter-Landau-level Coulomb interaction, which becomes more complex. Our results could be detected in the magneto-optical experiments.

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Zhigang Wang, Zhen-Guo Fu, Ping Zhang. 2012-04-18. Magnetoexcitons and optical absorption of bilayer-structured topological insulators. https://doi.org/10.1063/1.4704657

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