We experimentally demonstrated anisotropic damping of the magnetization dynamics in a highly ordered Heusler compound Co3−xFexSi (x = 1.0, 2.0, and 3.0). The field-swept ferromagnetic resonance linewidth as a function of the resonant frequency was measured to exclude extrinsic contributions from two-magnon scattering and inhomogeneous line-broadening. In L21-ordered Co2FeSi film, a wide variation in the intrinsic Gilbert damping constant from 0.0023 to 0.0061 was clearly observed in the (111) plane, where a weak uniaxial magnetic anisotropy was formed via low-temperature epitaxial growth. The large anisotropy of the Gilbert damping constant was suppressed by increasing x, which suppresses the half-metallicity in Co3−xFexSi films.

We experimentally investigated the crystallographic anisotropy of the intrinsic Gilbert damping constant in single crystalline Fe(001) film deposited on MgO(001) substrate. The frequency-domain ferromagnetic resonance (FMR) spectrum was measured at given external magnetic fields via a vector network analyzer. From the field-domain FMR linewidth obtained as a function of resonant frequency, the intrinsic Gilbert damping constants along the crystallographic axes in the (001) plane were successfully obtained by evaluating the extrinsic influence of two magnon scattering and inhomogeneity. A four-fold crystalline anisotropy of the intrinsic Gilbert damping constant, similar to the magnetic crystalline anisotropy in the (001) plane, was clearly observed. Furthermore, we found that the intrinsic Gilbert damping constant along the easy axis was smaller than that along the hard axis.

We demonstrate the time-resolved real-space observation of vortex gyration in a magnetic circular disc by X-ray magnetic circular dichroism photoemission microscopy at the SPring-8 beamline BL25SU, both with and without an additional structure called a pair tag, which serves to control the magnetic curling direction. By comparing the gyration orbits of the vortices, we found that the gyration properties are dependent on the presence of the additional structure in spite of the discs having the same diameter. Furthermore, we reproduced the vortex gyration by micromagnetic simulation. The confinement potential of the vortex can be controlled by the additional structure.

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We experimentally demonstrated electrical detection of All-Optical magnetization switching (AOS) induced by a single femtosecond laser pulse irradiation by measuring alternate rapid changes in anomalous Hall voltage and magneto-optic image pulse by pulse in a Hall-cross shape ferrimagnetic GdFeCo alloy thin film. We also demonstrated that the amplitude of the change in anomalous Hall voltage depended on the position of the AOS-created magnetic domain on the Hall cross. Furthermore, the AOS-created magnetic domains were stable against subsequent current applications in the Hall cross circuit, whereas reversed magnetic domains were not created when the laser pulse was irradiated with a high current. We found that cooperative effect among magnetism, light, and electric current was assumed to have effects on absence of the AOS. Combined the AOS phenomenon and an electrical measurement/control techniques can realize ultrafast, deterministic, and distinguishable applications.