Bias current dependence of spin accumulation signals in a silicon channel detected by a Schottky tunnel contact

TL;DR

This study investigates how bias current influences the detection of spin accumulation signals in silicon channels using Schottky tunnel contacts, revealing bias-dependent detectability of spin-polarized electrons.

Contribution

It demonstrates the bias current dependence of spin signal detection in silicon devices with Schottky contacts, highlighting the conditions for effective electrical detection.

Findings

Hanle-effect curves observed only under forward bias

Electrical detectability higher in forward bias

Evidence of spin-polarized electrons in Si channel

Abstract

We study the electrical detection of spin accumulation at a ferromagnet-silicon interface, which can be verified by measuring a Hanle effect in three-terminal lateral devices. The device structures used consist of a semiconducting Si channel and a high-quality Schottky tunnel contact. In a low current-bias region, the Hanle-effect curves are observed only under forward bias conditions. This can be considered that the electrical detectability of the forward-biased contact is higher than that of the reverse-biased contact. This is possible evidence for the detection of spin-polarized electrons created in a Si channel.