Gate-dependent spin-torque in a nanoconductor-based spin-valve

TL;DR

This paper investigates how quantum interference effects in a nanoconductor-based spin-valve enable gate-controlled modulation of spin-torque, offering a new way to manipulate spin dynamics in nanoscale devices.

Contribution

It introduces a theoretical analysis of spin-torque modulation via gate voltage in a single-channel nanoconductor spin-valve, highlighting qualitative differences from multichannel systems.

Findings

Spin-torque can be modulated by gate voltage due to quantum interference.

Quantum effects lead to distinct behavior compared to disordered multichannel spin-valves.

Potential for experimental observation of gate-controlled spin-torque in nanoscale devices.

Abstract

This article discusses the spin-torque effect in a spin-valve made out of two ferromagnetic leads connected through a coherent nanoconductor (NC), in the limit where a single channel of the NC lies near the Fermi energy of the leads. Due to quantum interferences inside the NC, the spin-torque presents clear qualitative differences with respect to the case of a multichannel disordered spin-valve. In particular, it can be modulated with the NC gate voltage. In principle, this modulation can be observed experimentally, assuming that the spin-torque affects a ferromagnetic nano-domain in direct contact with the NC.