Manifestation of spin-orbit interaction in tunneling between 2D electron layers

An influence of spin-orbit interaction on the tunneling between two 2D electron layers is considered. Particular attention is addressed to the relation between the contribution of Rashba and Dresselhaus types. It is shown that without scattering of the electrons, the tunneling conductance can either exhibit resonances at certain voltage values or be substantially suppressed over the whole voltage range. The dependence of the conductance on voltage turns out to be very sensitive to the relation between Rashba and Dresselhaus contributions even in the absence of magnetic field. The elastic scattering broadens the resonances in the first case and restores the conductance to a larger magnitude in the latter one. These effects open possibility to determine the parameters of spin-orbit interaction and electrons scattering time in tunneling experiments with no necessity of external magnetic field

Weak localization of holes in high-mobility heterostructures

Theory of weak localization is developed for two-dimensional holes in semiconductor heterostructures. Ballistic regime of weak localization where the backscattering occurs from few impurities is studied with account for anisotropic momentum scattering of holes. The transition from weak localization to anti-localization is demonstrated for long dephasing times. For stronger dephasing the conductivity correction is negative at all hole densities due to non-monotonous dependence of the spin relaxation time on the hole wavevector. The anomalous temperature dependent correction to the conductivity is calculated. We show that the temperature dependence of the conductivity is non-monotonous at moderate hole densities.Comment: 5 pages, 4 figure

Deduction of Pure Spin Current from Spin Linear and Circular Photogalvanic Effect in Semiconductor Quantum Wells

We study the spin photogalvanic effect in two-dimensional electron system with structure inversion asymmetry by means of the solution of semiconductor optical Bloch equations. It is shown that a linearly polarized light may inject a pure spin current in spin-splitting conduction bands due to Rashba spin-orbit coupling, while a circularly polarized light may inject spin-dependent photocurrent. We establish an explicit relation between the photocurrent by oblique incidence of a circularly polarized light and the pure spin current by normal incidence of a linearly polarized light such that we can deduce the amplitude of spin current from the measured spin photocurrent experimentally. This method may provide a source of spin current to study spin transport in semiconductors quantitatively