Spin relaxation in Rashba rings

Spin relaxation dynamics in rings with Rashba spin-orbit coupling is investigated using spin kinetic equation. We find that the spin relaxation in rings occurs toward a persistent spin configuration whose final shape depends on the initial spin polarization profile. As an example, it is shown that a homogeneous parallel to the ring axis spin polarization transforms into a persistent crown-like spin structure. It is demonstrated that the ring geometry introduces a geometrical contribution to the spin relaxation rate speeding up the transient dynamics. Moreover, we identify several persistent spin configurations as well as calculate the Green function of spin kinetic equation

Influence of Nuclear Spin Polarization on Quantum Wire Conductance

In this work, we study a possibility to measure the transverse and longitudinal relaxation times of a collection of polarized nuclear spins located in the region of a quantum wire via its conductance. The interplay of an external in-plane magnetic field, spin-orbit interaction, and the changing field of the spin-polarized nuclei cause the conductance of the quantum wire to evolve in time. We show that it is possible to extract the transverse and longitudinal relaxation times of the spin-polarized nuclei from the time dependence of the conductance.Comment: Presented at the 2004 IEEE NTC Quantum Device Technology Worksho