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arXiv · 2105.04167

Role of higher-order effects in spin-misalignment small-angle neutron scattering of high-pressure torsion nickel

Yojiro Oba·Mathias Bersweiler·Ivan Titov·Nozomu Adachi·Yoshikazu Todaka·Elliot Paul Gilbert·Nina-Juliane Steinke·Konstantin L. Metlov·Andreas Michels
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Abstract

Magnetic-field-dependent unpolarized small-angle neutron scattering (SANS) experiments demonstrate that high-pressure torsion (HPT) straining induces spin misalignments in pure Ni, which persist in magnetic fields up to 4 T. The spin-misalignment scattering patterns are elongated perpendicular to the applied magnetic field due to an unusual predominant longitudinal $sin^2(\theta)$-type angular anisotropy. Such a contribution cannot be explained by the conventional second order (in spin misalignment amplitude) micromagnetic SANS theory in the approach-to-saturation regime, nor can its magnitude relative to the other features of the cross sections by the third order micromagnetic SANS theory. This indicates that the high-density of crystal defects induced via HPT straining in Ni makes such higher-order effects in the micromagnetic SANS cross sections observable.

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Yojiro Oba, Mathias Bersweiler, Ivan Titov, Nozomu Adachi, Yoshikazu Todaka, Elliot Paul Gilbert, Nina-Juliane Steinke, Konstantin L. Metlov, Andreas Michels. 2021-05-10. Role of higher-order effects in spin-misalignment small-angle neutron scattering of high-pressure torsion nickel. https://doi.org/10.1103/physrevmaterials.5.084410

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