# Micromagnetic simulations of spin-torque driven magnetisation dynamics with spatially resolved spin transport and magnetisation texture

## TL;DR

This paper introduces a fast simulation method coupling spin transport and micromagnetics to accurately model spin-torque driven magnetisation dynamics in nano-structures, aligning well with experimental results.

## Contribution

A novel coupling approach between spin transport and micromagnetics for realistic, spatially resolved simulations of spin-torque phenomena in nano-pillar devices.

## Key findings

- Accurately reproduces spin-wave mode excitation and threshold currents.
- Matches experimental observations of magnetoresistance and switching.
- Provides insights into spin-caloritronics device behavior.

## Abstract

We present a simple and fast method to simulate spin-torque driven magnetisation dynamics in nano-pillar spin-valve structures. The approach is based on the coupling between a spin transport code based on random matrix theory and a micromagnetics finite-elements software. In this way the spatial dependence of both spin transport and magnetisation dynamics is properly taken into account. Our results are compared with experiments. The excitation of the spin-wave modes, in- cluding the threshold current for steady state magnetisation precession and the nonlinear frequency shift of the modes are reproduced correctly. The giant magneto resistance effect and the magnetisa- tion switching also agree with experiment. The similarities with recently described spin-caloritronics devices are also discussed.