Browsing by Author "Honecker, D"

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    Magnetization reversal in Nd-Fe-B based nanocomposites as seen by magnetic small-angle neutron scattering
    (American Institute of Physics, 2013-01-14) Bick, JP; Honecker, D; Dobrich, F; Suzuki, K; Gilbert, EP; Frielinghaus, H; Kohlbrecher, J; Gavilano, J; Forgan, EM; Schweins, R; Lindner, P; Birringer, R; Michels, A
    We have studied the magnetization-reversal process of a Nd2Fe14B/Fe3B nanocomposite using small-angle neutron scattering. Based on the computation of the autocorrelation function of the spin misalignment, we have estimated the characteristic size l(C) of spin inhomogeneities around the Nd2Fe14B nanoparticles. The quantity l(C) approaches a constant value of about 12.5 nm (similar to average Nd2Fe14B particle radius) at 14 T and takes on a maximum value of about 18.5 nm at the coercive field of -0.55 T. The field dependence of l(C) can be described by a model that takes into account the convolution relationship between the nuclear and the magnetic microstructure. © 2013, American Institute of Physics
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    Topological barrier for skyrmion lattice formation in MnSi
    (Australian Institute of Nuclear Science and Engineering (AINSE), 2020-11-11) Leishman, A; Menezes, RM; Longbons, G; Bauer, ED; Janoschek, M; Honecker, D; Debeer-Schmitt, L; White, JS; Sokolova, AV; Milosevic, MV; Eskildsen, MR
    We report the observation of a topological skyrmion energy barrier through a hysteresis of the skyrmion lattice in the prototypical helimagnet MnSi. Measurements of the energy barrier were made using smallangle neutron scattering and a bespoke DC field coil to allow for high-precision hysteresis loops. Data has been analyzed using an adapted Preisach model to quantify the energy barrier for skyrmion formation and the magnetic behavior of the sample as a whole. This analysis was then compared with minimum-energy path analysis based on atomistic spin simulations to verify the topological nature of the barrier. This reveals that the skyrmion lattice in MnSi forms with an activation barrier of several eV and in domains that are several hundred skyrmions in size.