Temperature-dependent transport and spin accumulation in a quantum wire with Rashba spin-orbit interaction

We study the theory of temperature-dependent electron transport, spin polarization, and spin accumulation in a Rashba spin-orbit interaction (RSOI) quantum wire connected nonadiabatically to two normal conductor electrode leads. The influence of both the wire-lead connection and the RSOI on the electron transport is treated analytically by means of a scattering matrix technique and by using an effective free-electron approximation. Through analytical analysis and numerical examples, we demonstrate a simple way to design a sensitive spin-transfer switch that operates without applying any external magnetic fields or attaching ferromagnetic contacts. We also demonstrate that the antisymmetry of the spin accumulation can be destroyed slightly by the coupling between the leads and the wire. Moreover, temperature can weaken the polarization and smear out the oscillations in the spin accumulation.

National Natural Science Foundation of China 10574042 Specialized Research Fund for the Doctoral Program of Higher Education of China 20060542002 Hunan Provincial Natural Science Foundation of China 06JJ2097 This work was supported by National Natural Science Foundation of China (Grant No. 10574042), Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20060542002) and Hunan Provincial Natural Science Foundation of China (Grant No. 06JJ2097).