Towards coherent spin precession in pure-spin current

TL;DR

This paper demonstrates that using dual injectors in lateral spin valves enhances phase coherence in spin precession signals, revealing universal behavior across different materials and improving understanding of pure spin current dynamics.

Contribution

It introduces a novel method with dual injectors to detect genuine in-plane spin precession signals, showing improved phase coherence and universal behavior across various materials.

Findings

Enhanced phase coherence in spin precession with dual injectors.

Universal behavior of spin precession coherence as a function of normalized separation.

Detection of genuine in-plane precession signals from the Hanle effect.

Abstract

Non-local spin injection in lateral spin valves generates a pure spin current which is a diffusive flow of spins (i.e. spin angular momentums) with no net charge flow. The diffusive spins lose phase coherency in precession while undergoing frequent collisions and these events lead to a broad distribution of the dwell time in a transport channel between the injector and the detector. Here we show the lateral spin-valves with dual injectors enable us to detect a genuine in-plane precession signal from the Hanle effect, demonstrating the phase coherency in the in-plane precession is improved with an increase of the channel length. The coherency in the spin precession shows a universal behavior as a function of the normalized separation between the injector and the detector in material-independent fashion for metals and semiconductors including graphene.