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Epitaxial graphene (EG) on SiC is promising owing to a capability to produce high-quality film on a wafer scale. One of the remaining issues is microscopic thickness variation of EG near surface steps, which induces variations in its electronic properties and device characteristics. We demonstrate here that the variations of layer thickness and electronic properties are minimized by using microfabricated SiC substrates which spatially confines the epitaxy. This technique will contribute to the realization of highly reliable graphene devices.

Magnetic patterning of FeRh thin films of various shapes and dimensions by 2 MeV H and He ion microbeam irradiation was examined by X-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) at the photon energy of the Fe L3 absorption edge. The XMCD-PEEM images clearly show that the various magnetic patterns whose sizes are about 1–2 µm, can be successfully produced by controlling the scan condition and the size of the ion beam probe. Furthermore, the quantitative analysis of the XMCD-PEEM images reveals that the localized magnetization in the micrometer-sized magnetic patterns significantly depends on the irradiation ion fluence. In addition, the annealing condition is also found to be one of the predominant factors that determine the magnetic state even for the micrometer-sized magnetic patterns.

Epitaxial graphene on Si (GOS) using a heteroepitaxy of 3C-SiC/Si has attracted recent attention owing to its capability to fuse graphene with Si-based electronics. We demonstrate that the stacking, interface structure, and hence, electronic properties of GOS can be controlled by tuning the surface termination of 3C-SiC(111)/Si, with a proper choice of Si substrate and SiC growth conditions. On the Si-terminated 3C-SiC(111)/Si(111) surface, GOS is Bernal-stacked with a band splitting, while on the C-terminated 3C-SiC(111)/Si(110) surface, GOS is turbostratically stacked without a band splitting. This work enables us to precisely control the electronic properties of GOS for forthcoming devices.

Current-induced magnetic domain wall (DW) displacement in a Co/Ni nano-wire with perpendicular magnetic anisotropy was investigated in real space by photoemission electron microscopy (PEEM) for the first time. DW velocity determined from the PEEM observation was 40 m s(-1) for the current density of 2.5 × 10(12) A m(-2), which was consistent with the result obtained by the electrical measurement used in our previous reports.

The dynamics of magnetostatically coupled vortices in a pair of ferromagnetic micron-sized disks has been observed in real space by pump–probe time-resolved photoemission electron microscopy. It is found that the dynamics of paired vortices is affected by a magnetic dipolar interaction. The displacement of a vortex core from its equilibrium position in the paired vortices during the supply of a magnetic field pulse is smaller than that in the isolated vortex, which is in qualitative agreement with micromagnetic simulation results. Unexpectedly, two eigenfrequencies of the paired vortices are different from each other. When the separation distance between the paired disks is shorter, the difference between the two eigenfrequencies is larger.

Magnetic domain structure of L10-type FeNi is observed by angular dependent photoelectron emission microscopy. It reveals the perpendicular magnetic component in magnetic domain structure with Bloch wall. The formation of Bloch wall is ascribed to the large magnetic anisotropy energy of L10-FeNi.

Graphene is a promising material in next-generation devices. Large-scale epitaxial graphene should be grown on Si substrates to transfer the accumulated technologies to integrated devices. We have for this reason developed epitaxy of graphene on Si (GOS) and device operation of the backgate field-effect transistors (FETs) using GOS has been confirmed. It is demonstrated in this paper that the GOS method enables us to tune the structural and electronic properties of graphene in terms of the crystallographic orientation of the Si substrate. Furthermore, it is shown that the uniformity of the GOS process within a sizable area enables us to reliably fabricate topgate FETs using conventional lithography techniques. GOS can be thus the key material in next-generation devices owing to the tunability of the electronic structure by the crystallographic orientation of the Si substrate.