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arXiv · 0709.4330

Magneto-gyrotropic photogalvanic effects in GaN/AlGaN two-dimensional systems

W. Weber·S. Seidl·S. N. Danilov·W. Prettl·V. V. Bel'kov·L. E. Golub·E. L. Ivchenko·Z. D. Kvon·Hyun-Ick Cho·Jung-Hee Lee·S. D. Ganichev
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Abstract

The magneto-gyrotropic photogalvanic and spin-galvanic effects are observed in (0001)-oriented GaN/AlGaN heterojunctions excited by terahertz radiation. We show that free-carrier absorption of linearly or circularly polarized terahertz radiation in low-dimensional structures causes an electric photocurrent in the presence of an in-plane magnetic field. Microscopic mechanisms of these photocurrents based on spin-related phenomena are discussed. Properties of the magneto-gyrotropic and spin-galvanic effects specific for hexagonal heterostructures are analyzed.

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W. Weber, S. Seidl, S. N. Danilov, W. Prettl, V. V. Bel'kov, L. E. Golub, E. L. Ivchenko, Z. D. Kvon, Hyun-Ick Cho, Jung-Hee Lee, S. D. Ganichev. 2007-09-27. Magneto-gyrotropic photogalvanic effects in GaN/AlGaN two-dimensional systems. https://doi.org/10.1016/j.ssc.2007.09.035

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