43 citations · 205 across the 12 of their papers we have counts for
12 papers
Two types of magnetic bubbles in MnNiGa observed via Lorentz microscopy
Hiroshi Nakajima, Atsuhiro Kotani, Ken Harada +1
Magnetic bubbles are remarkable spin structures that developed in uniaxial magnets with strong magnetocrystalline anisotropy. Several contradictory reports have been published conc…
Magnetic textures in a hexaferrite thin film and their response to magnetic fields revealed by phase microscopy
Atsuhiro Kotani, Ken Harada, Marek Malac +3
We investigated magnetic textures in a Sc-doped hexaferrite film by means of phase microscopy (PM) with a hole-free phase plate in a transmission electron microscope. In a zero mag…
Magnetic bubbles in an M-type hexagonal ferrite observed by hollow-cone Foucault imaging and small-angle electron diffraction
Atsuhiro Kotani, Hiroshi Nakajima, Atsushi Kawaguchi +5
We report hollow-cone imaging and small-angle electron diffraction of nanoscale magnetic textures such as magnetic-striped domains and magnetic bubbles of M-type hexagonal ferrite…
Lorentz microscopy and small-angle electron diffraction study of magnetic textures in LaSrMnO (0.15 0.30): the role of magnetic anisotropy
A. Kotani, H. Nakajima, K. Harada +2
Magnetic textures in the ferromagnetic phases of LaSrMnO for 0.15 0.30 have been investigated by Lorentz microscopy combined with small-angle electron diffr…
Field-temperature phase diagram of magnetic bubbles spanning chargeorbital ordered and metallic phases in LaSrMnO ()
A. Kotani, H. Nakajima, K. Harada +2
We report formation of magnetic textures in the ferromagnetic (FM) phase of LaSrMnO for 0.125; these textures are magnetic bubbles, magnetic stripe domains, a…
Formation mechanisms of magnetic bubbles in an M-type hexaferrite: the role of chirality reversals at domain walls
H. Nakajima, A. Kotani, K. Harada +2
We examined the formation mechanisms of magnetic bubbles in an M-type hexaferrite via Lorentz microscopy. When magnetic fields were perpendicularly applied to a thin sample of BaFe…
Observation of magnetic domain and bubble structures in magnetoelectric SrCoFeO
H. Nakajima, H. Kawase, K. Kurushima +3
The magnetic domain and bubble structures in the Z-type hexaferrite SrCoFeO were investigated using Lorentz microscopy. This hexaferrite exhibits a room-tempe…
Observation of magnetic domains in uniaxial magnets via small-angle electron diffraction and Foucault imaging
Hiroshi Nakajima, Atsuhiro Kotani, Ken Harada +1
Observation of magnetic domains is important in understanding the magnetic properties of magnetic materials and devices. In this study, we report that the magnetic domains of M-typ…
Foucault imaging and small-angle electron diffraction in controlled external magnetic fields
Hiroshi Nakajima, Atsuhiro Kotani, Ken Harada +2
We report a method for acquiring Foucault images and small-angle electron diffraction patterns in external magnetic fields using a conventional transmission electron microscope wit…
Electron diffraction covering a wide angular range from Bragg diffraction to small-angle diffraction
Hiroshi Nakajima, Atsuhiro Kotani, Ken Harada +1
We construct an electron optical system to investigate Bragg diffraction (the crystal lattice plane, - rad) with the objective lens turned off by adjusting the cu…
Formation process of skyrmion lattice domain boundaries: The role of grain boundaries
Hiroshi Nakajima, Atsuhiro Kotani, Masahito Mochizuki +2
We report on the formation process of skyrmion lattice (SkL) domain boundaries in FeGe using Lorentz transmission electron microscopy and small-angle electron diffraction. We obser…
Ferromagnetic Cluster Glass Phase Embedded in a Paramagnetic and Metallic Host in Non-uniform Magnetic System CaRu_{1-x}Sc_{x}O_{3}
Takafumi D. Yamamoto, Atsuhiro Kotani, Hiroshi Nakajima +4
We have investigated both static and dynamic magnetic properties of polycrystalline CaRuScO system in order to clarify the role of Sc ions as a disorder for mag…