Enhancement of spin accumulation in ballistic transport regime

Spin Transport Goes Ballistic

The circuits in today’s computers, cell-phone cameras, and many other electronic devices rely on the manipulation of electronic charges via CMOS technology—transistors built from a combination of “complementary” metal, oxide, and semiconductor materials. A promising “beyond-CMOS” technology [1] is spintronics, in which information is carried by spin instead of charge. Spintronics devices could ...

Ballistic spin transport in exciton gases

Ballistic spin transport without net charge transport in quantum wells

We demonstrate the ballistic transport of electron spin in the absence of net transport of electron charge. Spin-up electrons move in one direction, while an equal number of spin-down electrons move with the same velocities in the opposite direction, yielding no net charge motion. This effect, also referred to as a ‘pure’ spin current, results from the quantum mechanical interference of the tra...

Non-Ohmic Coulomb drag in the ballistic electron transport regime

We work out a theory of the Coulomb drag current created under the ballistic transport regime in a one-dimensional nanowire by a ballistic non-Ohmic current in a nearby parallel nanowire. As in the Ohmic case, we predict sharp oscillation of the drag current as a function of gate voltage or the chemical potential of electrons. We also study dependence of the drag current on the voltage V across...

Nonequilibrium spin Hall accumulation in ballistic semiconductor nanostructures.

We demonstrate that the flow of a longitudinal unpolarized current through a ballistic two-dimensional electron gas with Rashba spin-orbit coupling will induce a nonequilibrium spin accumulation which has opposite signs for the two lateral edges and is, therefore, the principal observable signature of the spin Hall effect in two-probe semiconductor nanostructures. The magnitude of its out-of-pl...