Current-Induced Nanomagnet Dynamics for Magnetic Fields Perpendicular to the Sample Plane

TL;DR

This paper investigates high-frequency magnetic dynamics in nanopillar devices driven by spin-polarized currents with magnetic fields perpendicular to the layers, revealing various precessional modes and static states.

Contribution

It provides experimental measurements and theoretical validation of spin-transfer torque effects in perpendicular magnetic fields in nanopillar structures.

Findings

Identification of multiple precessional modes and static states

Validation of spin-transfer torque theory through numerical simulations

Detailed phase diagram of magnetic dynamics

Abstract

We present electrical measurements of high-frequency magnetic dynamics excited by spin-polarized currents in Co/Cu/Ni80Fe20 nanopillar devices, with a magnetic field applied perpendicular to the sample layers. As a function of current and magnetic field, the dynamical phase diagram contains several distinguishable precessional modes and also static magnetic states. Using detailed comparisons with numerical simulations, we provide rigorous tests of the theory of spin-transfer torques.