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arXiv · 2410.22447

Symmetry-designed BiFeO3 single domain spin cycloid for efficient spintronics

Abstract

Deterministic control of coupled ferroelectric and antiferromagnetic orders remains a central challenge in multiferroics, limiting their integration into functional magnetoelectrics and magnonic-devices. (111)pc BiFeO3 with a robust single spin cycloid, offers direct magnetoelectric-coupling and a platform for efficient spin transport, yet multi-magnetic domains and ferroelectric-fatigue have prevented reproducible control. Here, we show that anisotropic-compressive in-plane strain stabilizes a single antiferromagnetic domain with unique spin-cycloid vector, by breaking the symmetry of the (111)pc plane. Epitaxial BiFeO3 films grown on orthorhombic NdGaO3 (011)o [(111)pc] substrates impose the required anisotropic in-plane strain and stabilizes single antiferromagnetic domain, as confirmed through direct imaging with scanning NV microscopy and non-resonant-x-ray-magnetic-scattering. Remarkably, these engineered films exhibit deterministic and non-volatile 180° switching of ferroelectric and single antiferromagnetic domains over 1,000 cycles. The monodomain state also enables anisotropic and threefold enhanced magnon transport with reduced scattering. Thus, symmetry-designed (111)pc monodomain BiFeO3 offers a robust platform for advanced magnetoelectric and magnonic applications.

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BibTeXRIS

Pratap Pal, Jonathon L. Schad, Anuradha M. Vibhakar, Shashank Kumar Ojha, Sajid Hussain Gi-Yeop Kim, Saurav Shenoy, Fei Xue, Kaushik Das, Yogesh Kumar, Paul Lenharth, A. Bombardi, Sayeef Salahuddin, Roger D. Johnson, Si-Young Choi, Mark S. Rzchowski, Long-Qing Chen, Ramamoorthy Ramesh, Paolo G. Radaelli, Chang-Beom Eom. 2025-10-09. Symmetry-designed BiFeO3 single domain spin cycloid for efficient spintronics. https://arxiv.org/abs/2410.22447

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