Inverted current-driven switching in Fe(Cr)/Cr/Fe(Cr) nanopillars

TL;DR

This paper investigates the electrical switching behavior in Fe(Cr)/Cr/Fe(Cr) nanopillars, revealing an inverted current-driven switching phenomenon linked to electron scattering properties at the interfaces.

Contribution

It demonstrates experimentally and theoretically that Fe(Cr)/Cr/Fe(Cr) trilayers exhibit inverted current-driven switching, a novel behavior in magnetic nanopillars.

Findings

Inverted switching observed with positive current from fixed to free layer

Normal magnetoresistance with resistance decreasing at high magnetic fields

Scattering differences in Fe(Cr) alloys influence switching behavior

Abstract

From both theory and experiment, scattering of minority electrons is expected to be weaker than scattering of majority electrons in both dilute Fe(Cr) alloys and at Fe(Cr)/Cr interfaces. We show that Fe(Cr)/Cr/Fe(Cr) trilayer nanopillars display a normal magnetoresistance--i.e., largest resistance at low magnetic fields and smallest at high fields, but an inverted current-driven switching--i.e., positive current flowing from the fixed to the reversing layer switches the trilayer from higher to lower resistance, and negative current switches it from lower to higher.