Work

Strain engineering of altermagnetic symmetry in epitaxial RuO 2 films

Year: 2026

Type: article

Abstract: The magnetic ground state of RuO$_2$ has been under intense debate. Using first-principles calculations, we show that compressive strain along [001] direction stabilizes an altermagnetic phase in RuO$_2$ thin films grown on (100) and (110) TiO$_2$ substrates. We further identify that compressive strain enhances the density of states near the Fermi level, resulting in a Fermi surface instability and the emergence of altermagnetism. The magnitude of strain and the associated increase in the density of states can be tuned by varying the film thickness, as systematically confirmed by x-ray diffraction and photoemission spectroscopy measurements. Symmetry analysis further reveals that (100) RuO$_2$ hosts an ideal altermagnetic order, whereas broken symmetry in (110) films leads to an uncompensated ferrimagnetic state. Finally, we discuss the effects of Hubbard $U$ parameters and evaluate the realistic tunneling magnetoresistance of (100) RuO$_2$.

Source: Physical review. B./Physical review. B

DOI: 10.1103/llqj-z28s

Authors: Johnathas D. S. Forte, Seung Gyo Jeong, Anand Santhosh, Seungjun Lee, Bharat Jalan, Tony Low

Institutions: University of Minnesota, Kyung Hee University

Language: English

Topic: Magnetic properties of thin films

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Kyung Hee University, Multidisciplinary University Research Initiative, Air Force Office of Scientific Research

Awards: G1523888516, G2859732023, G5933335244