Spin-Galvanic Effect and Spin Orientation Induced Circular Photogalvanic Effect in Quantum Well Structures

Abstract

The spin-galvanic effect and the spin polarization induced circular photogalvanic effect generated by homogeneous optical excitation with circularly polarized radiation in quantum wells (QWs) are reviewed. In both effects the current flow is driven by an asymmetric distribution of spin polarized carriers in k-space of systems with lifted spin degeneracy due to k-linear terms in the Hamiltonian. Spin photocurrents provide methods to investigate spin relaxation in the condition of monopolar spin orientation and to conclude on the in-plane symmetry of QWs.