The magnetic properties of bulk RuO2 remain a subject of active debate, despite its pivotal role in the emergence of altermagnetism. The latter is a novel paradigm in magnetic phases, characterized by the absence of net magnetization due to anti-parallel alignment of magnetic moments, yet displaying finite spin-splitting in the electronic band structure. This unique behavior unlocks opportunities for advanced applications in information technology devices. Recent experimental and theoretical investigations suggest that bulk RuO2, contrary to prior assumptions, is non-magnetic. In this work, we propose the fabrication of RuO2 thin films to robustly stabilize the altermagnetic phase. Unlike their bulk counterparts, thin films experience substantial strain relaxation, leading to a dramatic impact on the electronic structure that triggers a transition towards an altermagnetic behavior, which mimics the impact of an artificially applied Hubbard-U correction to account for electronic correlations. Our findings promote the use and exploration of thin films for the realization of spintronic devices based on altermagnets.
@article{arxiv.2412.15377,
title = {Confinement-induced altermangetism in RuO$_2$ thin films},
author = {Samy Brahimi and Dibya Prakash Rai and Samir Lounis},
journal= {arXiv preprint arXiv:2412.15377},
year = {2024}
}