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arXiv · 1711.07840

Multiphoton excitation and high-harmonics generation in topological insulator

H. K. Avetissian·A. K. Avetissian·B. R. Avchyan·G. F. Mkrtchian
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Abstract

Multiphoton interaction of coherent electromagnetic radiation with 2D metallic carriers confined on the surface of the 3D topological insulator is considered. A microscopic theory describing the nonlinear interaction of a strong wave and metallic carriers with many-body Coulomb interaction is developed. The set of integrodifferential equations for the interband polarization and carrier occupation distribution is solved numerically. Multiphoton excitation of Fermi-Dirac sea of 2D massless carriers is considered for a THz pump wave. It is shown that in the moderately strong pump wave field along with multiphoton interband/intraband transitions the intense radiation of high harmonics takes place.

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H. K. Avetissian, A. K. Avetissian, B. R. Avchyan, G. F. Mkrtchian. 2017-11-20. Multiphoton excitation and high-harmonics generation in topological insulator. https://doi.org/10.1088/1361-648x%2Faab989

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