Feedback control of noise in spin valves by the spin-transfer torque

TL;DR

This paper demonstrates how spin-transfer torque can be used to suppress thermal noise in magnetic spin valves, improving their stability and fidelity with reduced power consumption.

Contribution

It introduces a control scheme using current-induced spin-transfer torque to stabilize magnetic layers and reduce power without sacrificing performance.

Findings

Spin-transfer torque effectively suppresses thermal fluctuations.

Power consumption can be minimized with simple resistance-based control.

Enhanced stability of magnetic read heads and memory elements.

Abstract

The miniaturisation of magnetic read heads and random access memory elements makes them vulnerable to thermal fluctuations. We demonstrate how current-induced spin-transfer torques can be used to suppress the effects of thermal fluctuations. This enhances the fidelity of perpendicular magnetic spin valves. The simplest realization is a dc current to stabilize the free magnetic layers. The power can be significantly reduced without losing fidelity by simple control schemes, in which the stabilizing current-induced spin-transfer torque is controlled by the instantaneous resistance.