Effect of Interlayer Coupling on Current-Assisted Magnetization Switching in Nanopillars

TL;DR

This paper investigates how interlayer magnetic coupling influences current-assisted magnetization switching in nanopillars, revealing that strong coupling can alter switching behavior from hysteretic to reversible, with implications for magnetic device design.

Contribution

It demonstrates that interlayer coupling significantly impacts switching behavior, introducing a simple thermal activation model to explain the effects.

Findings

Strong coupling changes hysteretic switching to reversible.

Dipole and RKKY couplings affect low-field switching.

Thermal activation over a barrier explains switching behavior.

Abstract

We show that dipole-field induced antiferromagnetic coupling, or RKKY ferromagnetic coupling, between Co layers can strongly affect the low magnetic field switching behavior of Co/Cu/Co nanopillars. Whereas current-assisted switching at low fields in uncoupled nanopillars is always hysteretic, strong coupling of either kind can change the switching to non-hysteretic (reversible). These differences can be understood with a simple picture of current-assisted thermal activation over a barrier.