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

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 نشر من قبل Thomas Tybell
 تاريخ النشر 2020
  مجال البحث فيزياء
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Antiferromagnetic thin films typically exhibit a multi-domain state, and control of the antiferromagnetic Neel 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 Neel 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 Neel vector is found along the tensile strained b axis, contrary to bulk LaFeO3 having the Neel 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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