Controlled normal and inverse magnetoresistance and current-driven magnetization switching in magnetic nanopillars

TL;DR

This paper demonstrates the ability to independently control and invert both the magnetoresistance and current-driven magnetization switching in magnetic nanopillars by using ferromagnetic metals with different scattering anisotropies, at room temperature and 4.2K.

Contribution

It introduces a method to invert magnetoresistance and switching directions independently in nanopillars using tailored ferromagnetic layers, expanding understanding of spin-dependent transport.

Findings

All four combinations of normal and inverse behaviors observed.

Switching direction is determined by the net scattering anisotropy of the fixed ferromagnet.

Inversion of magnetoresistance and switching is achievable at both room temperature and cryogenic conditions.

Abstract

Combining pairs of ferromagnetic metals with different signs of scattering anisotropies, let us independently invert the magnetoresistance and the direction of current-driven switching in ferromagnetic/non-magnetic/ferromagnetic metal nanopillars. We show all four combinations of normal and inverse behaviors, at both room temperature and 4.2K. In all cases studied, the direction of switching is set by the net scattering anisotropy of the fixed (polarizing) ferromagnet. We provide simple arguments for what we see.