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arXiv · 2011.12056

Uniaxial Néel Vector Control in Perovskite Oxide Thin Films by Anisotropic Strain Engineering

K. Kjærnes·I. Hallsteinsen·R. V. Chopdekar·M. Moreau·T. Bolstad·I-H. Svenum·S. M. Selbach·T. Tybell
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Abstract

Antiferromagnetic thin films typically exhibit a multi-domain state, and control of the antiferromagnetic Néel vector is challenging as antiferromagnetic materials are robust to magnetic perturbations. By relying on anisotropic in-plane strain engineering of epitaxial thin films of the prototypical antiferromagnetic material LaFeO3, uniaxial Néel vector control is demonstrated. Orthorhombic (011)- and (101)-oriented DyScO3, GdScO3 and NdGaO3 substrates are used to engineer different anisotropic in-plane strain states. The anisotropic in-plane strain stabilises structurally monodomain monoclinic LaFeO3 thin films. The uniaxial Néel vector is found along the tensile strained b axis, contrary to bulk LaFeO3 having the Néel vector along the shorter a axis, and no magnetic domains are found. Hence, anisotropic strain engineering is a viable tool for designing unique functional responses, further enabling antiferromagnetic materials for mesoscopic device technology.

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K. Kjærnes, I. Hallsteinsen, R. V. Chopdekar, M. Moreau, T. Bolstad, I-H. Svenum, S. M. Selbach, T. Tybell. 2020-11-24. Uniaxial Néel Vector Control in Perovskite Oxide Thin Films by Anisotropic Strain Engineering. https://doi.org/10.1103/physrevb.103.224435

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