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

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 نشر من قبل Sergey Ganichev
 تاريخ النشر 2007
  مجال البحث فيزياء
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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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