Small-angle neutron scattering signatures of magnetic hopfions
Abstract: Magnetic hopfions are three-dimensional localized magnetic topological solitons which can exist in the bulk of magnetic materials. Based on a Ritz model for magnetic hopfions in a chiral magnet, the unpolarized magnetic small-angle neutron scattering (SANS) cross section, the spin-flip scattering cross section, and the chiral function (characterizing the imbalance between the two spin-flip scattering amplitudes) are computed here analytically; while the real-space correlation function is obtained numerically. Features of these functions, specific to magnetic hopfions, are discussed. Our results enable the SANS method to be used for the detection of magnetic hopfions.
- L. D. Faddeev, Some comments on the many-dimensional solitons, Lett. Math. Phys. 1, 289–293 (1976).
- A. B. Borisov and V. Kiselev, Solitons and Localized Structures in Magnets (UB Press of RAS, Ekaterinburg, 2009/2011).
- Y. Liu, R. K. Lake, and J. Zang, Binding a hopfion in a chiral magnet nanodisk, Phys. Rev. B 98, 174437 (2018).
- P. Sutcliffe, Hopfions in chiral magnets, J. Phys. A: Math. Theor. 51, 375401 (2018).
- A. Michels, Magnetic Small-Angle Neutron Scattering: A Probe for Mesoscale Magnetism Analysis (Oxford University Press, Oxford, 2021).
- K. L. Metlov, Two types of metastable hopfions in bulk magnets, Physica D 443, 133561 (2023).
- J. H. C. Whitehead, An Expression of Hopf’s Invariant as an Integral, Proc. Natl. Acad. Sci. U.S.A. 33, 117–123 (1947).
- K. L. Metlov, Magnetostatic bounds on stability of hopfions in bulk helimagnets (2024a), arXiv:2404.07964 [cond-mat.mes-hall] .
- K. L. Metlov, Source code, https://github.com/metlov/magnhopf (2024b).
- S. V. Maleev, Polarized neutron scattering in magnets, Physics–Uspekhi 45, 569–596 (2002).
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