Temperature dependence of spin diffusion length in silicon by Hanle-type spin precession

TL;DR

This study investigates how temperature affects the spin diffusion length in silicon using Hanle-type spin precession, revealing that interface effects mainly cause temperature dependence of non-local signals.

Contribution

It demonstrates the temperature dependence of spin diffusion length in silicon and separates interface and bulk effects, highlighting interface spin polarization reduction as the main factor.

Findings

Spin diffusion length agrees across Hanle and gap dependence methods.

Temperature dependence mainly due to interface spin polarization reduction.

Interface effects are the major source of temperature-dependent non-local signals.

Abstract

The Hanle-type spin precession method was carried out associated with non-local magnetoresistance measurement using a highly doped (5\times10^19) silicon channel. The spin diffusion length obtained by the Hanle-method is in good agreement with that by the gap dependence of non-local signals. We have evaluated the interface and bulk channel effects separately, and it was demonstrated that the major source of temperature dependence of non-local signals originates from the spin polarization reduction at interface between the tunnel barrier and silicon.