Simultaneous field-induced strain and strain-engineered magnetization establish non-collinear AFM UO<sub>2</sub> as the strongest known piezomagnet.

ORAL

Abstract

Actinide materials have various applications that range from nuclear energy to quantum computing. Robust piezomagnetism (PZM), a rare property of non-collinear antiferromagnetic materials that could enable control of a magnetic field by an electric field in hybrid piezoelectric/piezomagnetic devices, was first suggested in UO2 from strain measurements in very large magnetic fields below the Néel temperature TN = 30 K [1]. Confirmation of PZM requires, however, observation of the reciprocal property, i.e. strain-induced magnetization. Recent results demonstrate the feasibility of strain engineering in UO2 epitaxial thin films and explore the origin of induced ferromagnetism [2]. It is found that UO2+x thin films are hypo-stoichiometric (x<0) with in-plane tensile strain, while they are hyper-stoichiometric (x>0) with in-plane compressive strain. In addition to establishing PZM in UO2, this work reveals the correlation among strain, point defects, and ferromagnetism in strain-engineered UO2+x thin films. The results offer new opportunities to understand the influence of coupled order parameters on the emergent properties of actinide thin films. [1] M. Jaime et al., Nat. Comm. 8, 99 (2017). [2] Y. Sharma et al., Adv. Sci. 2203473 (2022).

*The U.S. Department of Energy Office of Basic Energy Sciences, Materials Sciences, and Engineering Division project "Actinide materials under extreme conditions" supported work by K.G. The NHMFL Pulsed Field Facility is supported by the NSF, the U.S. D.O.E., and the State of Florida through NSF cooperative grant DMR-212 1157490. Work by M.J. was supported by the U.S. D.O.E. BES project "Science at 100 Tesla". The work at Los Alamos National Laboratory was supported by the NNSA's Laboratory Directed Research and Development (LDRD) Program and was performed, in part, at the Center for Integrated Nanotechnologies (CINT), an Office of Science User Facility operated for the U.S. Department of Energy Office of Science. Los Alamos National Laboratory, an affirmative action-equal opportunity employer, was managed by Triad National Security, LLC for the U.S. Department of Energy's NNSA, under contract 89233218CNA000001. R.S. and Y.S. acknowledge support from the G. T. Seaborg Institute.

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Publication: [1] M. Jaime et al., Nat. Comm. 8, 99 (2017).
[2] Y. Sharma et al., Adv. Sci. 2203473 (2022).

Presenters

  • Marcelo Jaime

    • Los Alamos Natl Lab
    • Los Alamos National Laboratory

Authors

  • Marcelo Jaime

    • Los Alamos Natl Lab
    • Los Alamos National Laboratory

  • Yogesh Sharma

    • Oak Ridge National Laboratory

  • Amanda Huon

    • Oak Ridge National Laboratory
    • Saint Joseph's University

  • Mathew M Schneider

    • Los Alamos National Laboratory

  • Rico Schoenemann

    • Los Alamos National Laboratory

  • Michael Fitzsimmons

    • University of Tennessee

  • Andres Saul

    • Aix-Marseilles University
    • Aix-Marseille University

  • Myron B Salamon

    • University of Texas at Dallas

  • Krzysztof Gofryk

    • Idaho National Laboratory
    • Idaho National Labs

  • Aiping Chen

    • Los Alamos National Laboratory
    • lanl
    • Los Alamos National Lab
    • Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM 87545, USA