Internal effective field sources for spin torque nano pillar oscillators

TL;DR

This study uses micromagnetic modeling to explore internal field sources in spin torque nano pillar oscillators, aiming to replace external fields with tunable internal mechanisms based on geometry and material properties.

Contribution

It introduces an expanded micromagnetic model incorporating spin torque and impedance, evaluating internal field sources through three methods and comparing results with analytical predictions.

Findings

Internal field sources can be tuned via geometry and material properties.

The methods show consistent frequency shifts with analytical models.

Temperature dependence affects the internal field sources.

Abstract

In this paper we numerically conduct micromagnetic modelling with an expended micromagnetic model that includes the spin torque term and an impedance model to investigate methods to replace external field sources with internal ones and to investigate its tuneability on nanopillar geometries. We present results for three methods: interlayer coupling, large perpendicular anisotropy and magnetostatic coupling. The internal field sources are evaluated as function of frequency shift with current, its dependency on temperature and are tested against analytical predictions.