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DOE OSTI · 3739804

Long-range magnetic order and relaxor ferroelectricity in a hexagonal high-entropy ferrite

Miertschin, Duncan [Baylor University]·Kunwar, Sundar [Los Alamos National Laboratory (LANL)]·Regmi, Balaram [Baylor University]·Kandel, Poshan [Baylor University]·Thapa, Sanjib [Baylor University]·Crater, Davis [Baylor University]·Basso, Luca [Center for Integrated Nanotechnologies]·Dodson, Adam [ORNL]·Gai, Zheng [ORNL] (ORCID:0000000260994559)·Yao, Lide [Aalto University, Finland]·Chen, Yu-Wei [National Yang Ming Chiao Tung University]·Bencok, Peter [Diamond Light Source, Didcot, OX11 0DE, United Kingdom]·Kleibert, Armin [Paul Scherrer Institute]·Yen-Lin, Huang [National Chiao Tung University, Hsinchu, Taiwan]·Mounce, Andy [ORNL] (ORCID:0000000281152764)·Kotula, Paul G [Sandia National Laboratories (SNL)]·Dijken, Sebastiaan van [Aalto University, Finland]·Mazza, Alessandro R. [Los Alamos National Laboratory (LANL)]·Ward, Zac [ORNL] (ORCID:0000000210279186)·Shepelin, Nick [Paul Scherrer Institute]·Farhan, Alan [Baylor University]
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Abstract

Multiferroics that combine ferroelectricity and magnetic order are attractive for electronic and spintronic technologies, yet chemical disorder that promotes relaxor ferroelectricity usually suppresses long-range magnetic order. Here, we report entropy-stabilized relaxor multiferroicity in epitaxial hexagonal (Tb0.2Dy0.2Ho0.2Lu0.2Yb0.2)FeO3 thin films. Structural, magnetic, dielectric, and synchrotron spectroscopic measurements show the coexistence of relaxor ferroelectricity and long-range ferromagnetic order. We find that improper ferroelectricity remains robust against A-site configurational disorder, while the Fe sublattice preserves magnetic exchange. This separation of the microscopic origins of the polar and magnetic responses enables chemically disordered multiferroicity. Our results establish entropy engineering in hexagonal ferrites as a route toward multifunctional oxide thin films and provide a general design strategy for high-entropy multiferroics.

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Miertschin, Duncan [Baylor University], Kunwar, Sundar [Los Alamos National Laboratory (LANL)], Regmi, Balaram [Baylor University], Kandel, Poshan [Baylor University], Thapa, Sanjib [Baylor University], Crater, Davis [Baylor University], Basso, Luca [Center for Integrated Nanotechnologies], Dodson, Adam [ORNL], Gai, Zheng [ORNL] (ORCID:0000000260994559), Yao, Lide [Aalto University, Finland], Chen, Yu-Wei [National Yang Ming Chiao Tung University], Bencok, Peter [Diamond Light Source, Didcot, OX11 0DE, United Kingdom], Kleibert, Armin [Paul Scherrer Institute], Yen-Lin, Huang [National Chiao Tung University, Hsinchu, Taiwan], Mounce, Andy [ORNL] (ORCID:0000000281152764), Kotula, Paul G [Sandia National Laboratories (SNL)], Dijken, Sebastiaan van [Aalto University, Finland], Mazza, Alessandro R. [Los Alamos National Laboratory (LANL)], Ward, Zac [ORNL] (ORCID:0000000210279186), Shepelin, Nick [Paul Scherrer Institute], Farhan, Alan [Baylor University]. 2026-09-01. Long-range magnetic order and relaxor ferroelectricity in a hexagonal high-entropy ferrite. https://doi.org/10.1016/j.xcrp.2026.103526

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