Unusual Scaling of Kondo Spin Relaxation

Abstract

The relation between the Kondo spin relaxation rate ${{\tau }_{sK}}^{-1}$ and the Kondo momentum relaxation rate ${{\tau }_{eK}}^{-1}$ is explored by using nonlocal spin valves with submicron copper channels that contain dilute iron impurities. A linear relation between ${{\tau }_{sK}}^{-1}$ and ${{\tau }_{eK}}^{-1}$ is established under varying temperatures. However, under varying impurity concentrations, ${{\tau }_{sK}}^{-1}$ remains nearly constant despite variation of ${{\tau }_{eK}}^{-1}$ by a factor of 10. This surprising relation can be understood by considering spin relaxation through overlapping Kondo screening clouds and supports the physical existence of the elusive Kondo clouds.

References in corpus (2)

• Contribution of defects to the spin relaxation in copper nanowires
• Theory of Kondo suppression of spin polarization in nonlocal spin valves