カイラル磁性体における磁気スキルミオン格子構造の安定化

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The investigation of the stabilization of skyrmion-lattice was focused on two chiral materials: Cu2OSeO3 (ferromagnetic skyrmion), and CaBaCo2FeO7 (candidate for antiferromagnetic skyrmion). The dependence on the history and rate of temperature and field application when stabilizing the skyrmion-lattice in Cu2OSeO3 was evidenced. Furthermore, indications for higher order peaks were discovered. A new method was developed and applied successfully to discern these from double scattering. A manuscript has been prepared and can be expected later this year. The pursuit of more detailed effects lead to an improvement of the data reduction at the instrument TAIKAN, J-Parc. Applying the analysis techniques for Cu2OSeO3 helped discerning the impact of electric current on the skyrmion lattice in MnSi.The study of the general magnetic properties of CaBaCo2Fe2O7 was completed. Two types of order were separated using neutron scattering, a short range and a long range one. The first one is describable by a Heisenberg nearest neighbor model. Yet, the latter one shows additional precursors of a long-periodic spin structure, which were indeed found favorable using symmetry analysis. Another neutron experiment revealed the long range order to be a superposition of two periodic structures coexisting in a wide range of the AFM phase. While the longer periodic structure vanishes at lower temperatures, the remaining modulation resembles a skyrmion-lattice like spin structure. A manuscript on these features is in preparation. A key experiment was scheduled however postponed.