The B2-ordered alloy FeRh shows a metamagnetic phase transition, transforming from antiferromagnetic (AF) to ferromagnetic (FM) order at a temperature Tt∼380~K in bulk. As well as temperature, the phase transition can be triggered by many means such as strain, chemical doping, or magnetic or electric fields. Its first-order nature means that phase coexistence is possible. Here we show that a phase boundary in a 300~nm diameter nanopillar, controlled by a doping gradient during film growth, is moved by an electrical current in the direction of electron flow. We attribute this to spin injection from one magnetically ordered phase region into the other driving the phase transition in a region just next to the phase boundary. The associated change in resistance of the nanopillar shows memristive properties, suggesting potential applications as memory cells or artificial synapses in neuromorphic computing schemes.
@article{arxiv.1905.03573,
title = {Phase domain boundary motion and memristance in gradient-doped FeRh nanopillars induced by spin injection},
author = {Rowan C. Temple and Mark C. Rosamond and Jamie R. Massey and Trevor P. Almeida and Edmund H. Linfield and Damien McGrouther and Stephen McVitie and Thomas A. Moore and Christopher H. Marrows},
journal= {arXiv preprint arXiv:1905.03573},
year = {2024}
}