Spin relaxation mechanism in Silver nanowires covered with MgO protection layer

TL;DR

This study investigates spin relaxation in silver nanowires with MgO protective layers, demonstrating suppression of surface scattering and confirming the Elliott-Yafet mechanism with temperature-dependent behavior aligning with bulk metal scaling.

Contribution

It provides a detailed analysis of spin relaxation mechanisms in Ag nanowires with MgO coating, highlighting the suppression of surface scattering and confirming the Elliott-Yafet model in nanoscale systems.

Findings

MgO layer effectively suppresses surface scattering.

Spin relaxation follows Elliott-Yafet mechanism.

Temperature dependence aligns with Bloch-Grüneisen theory.

Abstract

Spin-flip mechanism in Ag nanowires with MgO surface protection layers has been investigated by means of nonlocal spin valve measurements using Permalloy/Ag lateral spin valves. The spin flip events mediated by surface scattering are effectively suppressed by the MgO capping layer. The spin relaxation process was found to be well described in the framework of Elliott-Yafet mechanism and then the probabilities of spin-filp scattering for phonon or impurity mediated momentum scattering is precisely determined in the nanowires. The temperature dependent spin-lattice relaxation follows the Bloch-Gr\"uneisen theory and falls on to a universal curve for the monovalent metals as in the Monod and Beuneu scaling determined from the conduction electron spin resonance data for bulk.