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arXiv · 2412.15377

Confinement-induced altermangetism in RuO$_2$ thin films

Samy Brahimi·Dibya Prakash Rai·Samir Lounis
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Abstract

The magnetic properties of bulk RuO$_2$ 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 RuO$_2$, contrary to prior assumptions, is non-magnetic. In this work, we propose the fabrication of RuO$_2$ 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.

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Samy Brahimi, Dibya Prakash Rai, Samir Lounis. 2024-12-19. Confinement-induced altermangetism in RuO$_2$ thin films. https://arxiv.org/abs/2412.15377

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