Related papers: Understanding spin transport from the motion in SU…
By generalizing the usual current density to a matrix with respect to spin variables, a general equation of continuity satisfied by the density matrix and current density matrix has been derived. This equation holds in arbitrary spin-orbit…
Spin and charge currents in systems with Rashba or Dresselhaus spin-orbit couplings are formulated in a unified version of four-dimensional SU(2)$\times$U(1) gauge theory, with U(1) the Maxwell field and SU(2) the Yang-Mills field. While…
We develop a drift-diffusion equation that describes electron spin polarization density in two-dimensional electron systems. In our approach, superpositions of spin-up and spin-down states are taken into account, what distinguishes our…
We find that in order to completely describe the spin transport, apart from spin current (or linear spin current), one has to introduce the angular spin current. The two spin currents respectively describe the translational and rotational…
For an electron, a spin-1/2 particle, the spin charge $\mathbf{s}$, a real pseudovector with constant length, could determine the spin polarization properties in quantum mechanics. Since spin density $\rho_{\mathbf{s}}$ could be expressed…
We discuss the Pauli Hamiltonian including the spin-orbit interaction within an U(1) x SU(2) gauge theory interpretation, where the gauge symmetry appears to be broken. This interpretation offers new insight into the problem of spin…
We find that in order to completely describe the spin transport, apart from spin current (or linear spin current), one has to introduce the angular spin current. The two spin currents respectively describe the translational and rotational…
The spin-orbit coupling systems with a zero magnetic field is studied under the equilibrium situation, {\it i.e.}, without a voltage bias. A persistent spin current is predicted to exist under most circumstances, although the persistent…
We present a simple and pedagogical derivation of the spin current as the linear response to an external electric field for both Rashba and Luttinger spin-orbital coupling Hamiltonians. Except for the adiabatic approximation, our derivation…
This article discusses spin transport in systems with spin-orbit interactions and how it can be understood in a semiclassical picture. I will first present a semiclassical wave-packet description of spin transport, which explains how the…
We derive the classical counterpart of a previously obtained quantum mechanical covariant ``continuitylike'' equation for the spin density, and present an intuitive picture for elucidating the non-conservation of the spin current. This…
We study the effect of electron-electron backscattering interactions on spin transport in a quantum wire. Even if these interactions have no significant effect on charge transport, they strongly influence the transport of spin. We use the…
We describe the spin and charge dynamics of the system of two electrons confined within a double quantum dot defined in a quantum wire. The spin dynamics is driven by the electron motion in presence of the spin-orbit interaction and the…
Space- and time-resolved measurements of spin drift and diffusion are performed on a GaAs-hosted two-dimensional electron gas. For spins where forward drift is compensated by backward diffusion, we find a precession frequency in absence of…
The Hamiltonian describing 2D electron gas, in a spin-orbit active medium, can be cast into a consistent non-Abelian gauge field theory leading to a proper definition of the spin current. The generally advocated gauge symmetric version of…
We develop a gauge theory for diffusive and precessional spin dynamics in two-dimensional electron gas with disorder. Our approach reveals a direct connections between the absence of the equilibrium spin current and strong anisotropy in the…
The conventional definition of spin-current, namely spin density multiplied by the group velocity, is not a conserved quantity due to possible spin rotations caused by spin-orbit (SO) interaction. However, in a model with spin-spin…
Based on kinetic equations for the density matrix, drift-diffusion equations are derived for a two-dimensional electron gas with Rashba spin-orbit coupling. Universal results are obtained for the weak coupling case. Most interesting is the…
Using response theory, we calculate the charge-current vortex generated by spin pumping at a point-like contact in a system with Rashba spin-orbit coupling. We discuss the spatial profile of the current density for finite temperature and…
Spin transport was studied in a two-dimensional electron gas hosted in a wide GaAs quantum well occupying two subbands. Using space and time Kerr rotation microscopy to image drifting spin packets under an in-plane accelerating electric…