April 22 - 26, 2024
Seattle, Washington
May 7 - 9, 2024 (Virtual)

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2024 MRS Spring Meeting
SF02.05.02

Strain-Driven Switching between Distinct Antiferromagnetic States in Frustrated Antiferromagnet UO2

When and Where

Apr 24, 2024
11:00am - 11:15am
Terrace Suite 2, Level 4, Summit

Presenter(s)

Co-Author(s)

Evgenia Tereshina-Chitrova1,Leonid Pourovskii2,3,Sergii Khmelevskyi4,Lukas Horak5,Thomas Gouder6,Roberto Caciuffo7

Institute of Physics, Czech Academy of Sciences1,École Polytechnique, Institut Polytechnique de Paris2,Collège de France, Université PSL3,Vienna Scientific Cluster Research Center, Vienna Technical University4,Faculty of Mathematics and Physics, Charles University5,European Commission, Joint Research Centre (JRC)6,National Institute for Nuclear Physics7

Abstract

Evgenia Tereshina-Chitrova1,Leonid Pourovskii2,3,Sergii Khmelevskyi4,Lukas Horak5,Thomas Gouder6,Roberto Caciuffo7

Institute of Physics, Czech Academy of Sciences1,École Polytechnique, Institut Polytechnique de Paris2,Collège de France, Université PSL3,Vienna Scientific Cluster Research Center, Vienna Technical University4,Faculty of Mathematics and Physics, Charles University5,European Commission, Joint Research Centre (JRC)6,National Institute for Nuclear Physics7
In materials containing magnetic atoms arranged in geometrically frustrated lattices, various magnetically ordered states can possess comparable energies with respect to the inter-site antiferromagnetic (AFM) exchange interactions. The concept of geometric frustration often intersects with broader phenomena in condensed matter physics, such as quantum spin liquids, topological states, and critical behaviour [1]. In recent decades, there has been a growing interest in intentionally manipulating magnetic states in collinear antiferromagnets, motivated by advancements in AFM spintronics [2]. In our study, we demonstrate the fundamental potential to control spin orientations in frustrated antiferromagnets, pawing the way for their utilization in realms of spintronics.<br/>Our research focuses on the interplay of magnetic and exchange anisotropy effects in artificial heterostructures based on a canonical frustrated <b>3-<i>k</i></b> antiferromagnet, UO<sub>2</sub>. We demonstrate that effective switching between the AFM states of different symmetries can be achieved by stretching the lattice of UO<sub>2</sub>. The phenomenon is probed experimentally using the exchange bias (EB) effect in stoichiometric UO<sub>2</sub>/Fe<sub>3</sub>O<sub>4</sub> bilayers. By employing many-body first-principles calculations based on the charge self-consistent Hubbard-I approximation [3,4] we identify magnetic configurations in the UO<sub>2</sub> layers. We show that a minor tetragonal distortion induces a transition between antiferromagnetic states of different symmetries, driven by appearance of a robust single-ion anisotropy. This impacts the arrangement of magnetic moments at the UO<sub>2</sub>/Fe<sub>3</sub>O<sub>4</sub> interface and thus influences the magnitude of exchange bias. Our findings showcase how epitaxial strain enables the manipulation of antiferromagnetic states in frustrated antiferromagnets by controlling single-site anisotropy.<br/><br/>We acknowledge the support of Czech Science Foundation under the grant no. 22-19416S. The samples were prepared in the framework of the EARL project of the European Commission Joint Research Centre, ITU Karlsruhe. Experiments were performed in MGML (mgml.eu), which is supported within the program of Czech Research Infrastructures (project no. LM2023065).<br/>[1] F. Giustino et al., J. Phys. Mater. 3 (2020) 042006<br/>[2] C. Marrows, Science 351 (2016) 558.<br/>[3] M. Aichhorn et al, Comp. Phys. Commun. 204 (2016) 200; J. Hubbard, Proc. Roy. Soc. (London) A 276 (1963) 238.<br/>[4] L. V. Pourovskii, Phys. Rev. B 94 (2016) 115117.

Keywords

actinide | magnetic properties | sputtering

Symposium Organizers

Edgar Buck, Pacific Northwest National Laboratory
Sarah Hernandez, Los Alamos National Laboratory
David Shuh, Lawrence Berkeley National Laboratory
Evgenia Tereshina-Chitrova, Czech Academy of Sciences

Session Chairs

Ladislav Havela
Alice Smith

In this Session