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Current induced local spin polarization due to the spin-orbit coupling in a two dimensional narrow strip
The current induced local spin polarization due to weak Rashba spin-orbit
coupling in narrow strip is studied. In the presence of longitudinal charge
current, local spin polarizations appear in the sample. The spin polarization
perpendicular to the plane has opposite sign near the two edges. The in-plane
spin polarization in the direction perpendicular to the sample edges also
appears, but does not change sign across the sample. From our scaling analysis
based on increasing the strip width, the out-of-plane spin polarization is
important mainly in a system of mesoscopic size, and thus appears not to be
associated with the spin-Hall effect in bulk samples.Comment: 4 pages, 4 figure
Optical Control of Topological Quantum Transport in Semiconductors
Intense coherent laser radiation red-detuned from absorption edge can
reactively activate sizable Hall type charge and spin transport in n-doped
paramagnetic semiconductors as a consequence of k-space Berry curvature
transferred from valence band to photon-dressed conduction band. In the
presence of disorder, the optically induced Hall conductance can change sign
with laser intensity.Comment: to appear in Phys. Rev. Let
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