Irradiative Control & Electrical Trigger of a Metamagnetic Phase Change for Ultra-High Speed Antiferromagnetic Spintronics
Dr. Steven P. Bennett
Naval Research Lab
Phase change materials have been a staple for a wide array of memory technologies for many decades. The promise of antiferromagnetic electronics has pushed the envelope past using a straight forward resistive phase change, to the realm of high speed spin flipping, incommensurate spin density waves and magnonics which can propagate without a local magnetic anisotropy to hinder spin rotation. In this new memory paradigm we will need to develop a new set of materials and understanding of spin physics from which to build this next generation of high speed and low energy loss devices. In this seminar I will provide an overview of my teams recent discoveries on how the metamagnetic transition in FeRh, from antiferromagnetic to ferromagnetic ordering, can be controlled and triggered using low energy heavy and light ion irradiation [1][2], as well as joule heating in confined wire device geometries at high switching speeds. We interrogate the complexities of these spin systems using polarized neutron scattering, revealing highly localized effects of ion irradiation in the films and uncover a new effect for metamagnetic spin dynamics which could be pivotally important for modern antiferromagnetic spintronics.
[1] S.P. Bennett et. Al., Coatings, 11(6), 661, (2021)
[2] C. D. Cress et. Al., ACS Appl. Mater. Interfaces 13, 1, 836–847, (2021)
email physics@nd.edu for zoom link