Abstract:

Spin photocurrents induced by optical excitation with circularly polarized radiation in semiconductors are reviewed. The absorption of circularly polarized light results in optical spin orientation due to the transfer of the angular momentum of photons to electrons, which causes a directed motion of electrons in unbiased semiconductors. A characteristic feature of this spin photocurrent is that it reverses its direction upon changing the radiation helicity. Three kinds of spin photocurrents, i.e., circular photogalvanic effect, anomalous circular photogalvanic effect and light-induced anomalous Hall effect, and their microscopic mechanisms are discussed. The important role of spin-orbit coupling is revealed.
 
 
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