Spin Polarized Transport and Spin Relaxation in Quantum Wires

摘要: We give an introduction to spin dynamics in quantum wires. After a review of spin-orbit coupling (SOC) mechanisms semiconductors, the diffusion equation with SOC is introduced. discuss particular conditions which solutions vanishing relaxation rates exist, where density forms persistent helices. overview mechanisms, emphasis on motional narrowing mechanism disordered conductors, D’yakonov–Perel’ relaxation. The solution wires shows that becomes diminished when reducing wire width below precession length L SO. This corresponds effective alignment field and formation helices whose form as well amplitude measure SOCs, linear Rashba Dresselhaus coupling. Cubic found yield diffusive undiminished contribution rate, however. recent experimental results confirm reduction rate. next theoretical proposals for creating spin-polarized currents T-shape structure Rashba-SOC. For relatively small SOC, high polarization can be obtained. However, corresponding conductance has been small. Due self-duality scattering matrix system interaction, no current obtained single-channel transport two-terminal devices. Therefore, one consider at least conductor three terminals. showing large if sufficiently strong. argue predicted effect should experimentally accessible InAs. possible realization InAs filters, see [1].