Spin and orbital mechanisms of the magnetogyrotropic photogalvanic effects in GaAs/AlxGa1−xAs quantum well structures

V. Lechner, L. E. Golub, F. Lomakina, V. V. Bel'kov, P. Olbrich, S. Stachel, I. Caspers, M. Griesbeck, M. Kugler, M. J. Hirmer, T. Korn, C. Schüller (+3 others)
2011 Physical Review B  
We report on the study of the linear and circular magneto-gyrotropic photogalvanic effect (MPGE) in GaAs/AlGaAs quantum well structures. Using the fact that in such structures the Land\'e-factor g* depends on the quantum well (QW) width and has different signs for narrow and wide QWs, we succeeded to separate spin and orbital contributions to both MPGEs. Our experiments show that, for most quantum well widths, the PGEs are mainly driven by spin-related mechanisms, which results in a
more » ... ts in a photocurrent proportional to the g* factor. In structures with a vanishingly small g* factor, however, linear and circular MPGE are also detected, proving the existence of orbital mechanisms.
doi:10.1103/physrevb.83.155313 fatcat:4nbhmp2s7bfpdm3wwjl3cmcnze