Quasi-two-dimensional spin transport wire

We demonstrate that in an inversion-asymmetric quasi-two-dimensional electron system (quasi2DES) with both Rashba and Dresselhaus spin-orbit couplings at present, certain transport directions on which no spin precession occurs can be found when the injected spin is properly polarized. By analyzing the expectation value of spin with respect the injected electron state on each space point in the quasi-2DES, we further show that adjacent regions with technically reachable widths along these directions exhibit nearly conserved spin. Hence a possible application in semiconductor spintronics, namely, spin transport wire is proposed.