A5115444792- Physics of Superconductivity and Magnetism
- Magnetic properties of thin films
- Quantum and electron transport phenomena
- Semiconductor Quantum Structures and Devices
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Advancements in Semiconductor Devices and Circuit Design
- Particle Detector Development and Performance
- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Magnetic Properties and Applications
- Plasma Diagnostics and Applications
- Superconducting Materials and Applications
- Electronic and Structural Properties of Oxides
- Electrodeposition and Electroless Coatings
- Semiconductor materials and interfaces
- Superconductivity in MgB2 and Alloys
- Theoretical and Computational Physics
- Electrohydrodynamics and Fluid Dynamics
- Surface and Thin Film Phenomena
- Electronic Packaging and Soldering Technologies
- Quantum Chromodynamics and Particle Interactions
- Acoustic Wave Resonator Technologies
- Silicon and Solar Cell Technologies
- Semiconductor materials and devices
Osaka Metropolitan University
2023-2024
Tokyo Metropolitan University
2023
Osaka City University
2010-2021
Tohoku University
2008
Kyoto University
1989-2003
Nagoya University
1960-1999
Chiba University
1994-1998
RIKEN
1994-1996
University of Tsukuba
1989-1994
Ube (Japan)
1991-1993
Strong intensity oscillations have been found in reflection high-energy electron diffraction during epitaxial growth of ${\mathrm{BaTiO}}_{3}$, ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$, and ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathit{x}}$ with perovskite-type structures. The oscillation period corresponds to the height minimum unit each oxide that satisfies chemical composition electrical neutrality. data provide a basic understanding process ionic oxides.
Magnetoresistance in high-quality single-crystal films of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{x}}$ studied a temperature range ${T}_{c}$\ensuremath{\lesssim}T\ensuremath{\lesssim}210 K is presented for magnetic field configurations both parallel and perpendicular to the conducting ab plane. The data are analyzed terms recent theories superconducting fluctuations considering orbital Zeeman effects Aslamazov-Larkin Maki-Thompson terms. From...
The orientation of YBa2Cu3O7−x thin films grown on (110) planes SrTiO3 by activated reactive evaporation was investigated means reflection high-energy electron diffraction. the depended substrate temperature. with parallel to surface grew in a narrow range temperatures around 530 °C, while (103) at above 600 °C. change epitaxial temperature is discussed terms dependence lattice mismatch between and SrTiO3.
We have, for the first time, made quasi-particle tunneling measurements on a YBa2Cu3O7−x(001)/Y2O3 (001)/YBa2 Cu3 O7−x (001)junction, which was epitaxially grown MgO(100) substrate in an in-situ process. Both layers of YBa2 showed same superconducting transition Tc end =86 K with ΔT(R=10–90%)=1.5 K. Quasi-particle direction perpendicular to Cu-O planes measured. A gap parameter Δ(4.5 K) 9.0±0.2 meV and value 2Δ/kTc 3.5+0.4−0.6 were obtained.
The electronic energy-band properties of epitaxially grown ${\mathrm{YBa}}_{2}$${\mathrm{CuO}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{x}}$(001) single-crystal thin films have been investigated by angle-resolved ultraviolet photoemission spectroscopy (ARUPS) with synchrotron radiation as the light source. (001) surfaces exhibit sharp (1\ifmmode\times\else\texttimes\fi{}1) low-energy electron-diffraction patterns. Our ARUPS data show a clear Fermi edge and dispersive nature valence...
The fundamental electrodynamical coupling processes between lightning and sprites are investigated. By combining the observed spectral data with Monte Carlo swarm experiments, reduced electric fields electron energies in sprite streamers halos estimated. obtained inside (70–97 Td an analysis error of ±5 Td) lower than conventional breakdown field, Ek ∼ 128 Td, indicating a significant reduction electrons associated while those (98–380 ±50 higher Ek, suggesting that ionization process drives...
Within the construct of complete Kim-Anderson model for critical-current density, we have calculated initial magnetization curves and full hysteresis loops type-II superconductors immersed in an external field H=${\mathit{H}}_{\mathrm{dc}}$+${\mathit{H}}_{\mathrm{ac}}$cos(\ensuremath{\omega}t), where ${\mathit{H}}_{\mathrm{dc}}$ (\ensuremath{\ge}0) is a dc bias ${\mathit{H}}_{\mathrm{ac}}$ (>0) ac amplitude. We denote maximum minimum values H by ${\mathit{H}}_{\mathit{A}}$...
The mechanical and superconducting properties of MgB2 wires heat treated at various conditions have been investigated. Superconducting wires, fabricated by the powder-in-tube (PIT) method, show a transition temperature Tc 32.4 K for as-rolled wire as shown dc-resistivity measurement. It is found that improved (37.3–38.4 K) subsequent Ar annealing treatment under sintering temperatures times. Remarkably, annealed samples significant improvement in overall quality samples. On 1323 0.6 ks, we...
The superconducting transition of a sintered ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{\mathrm{y}}$ pellet with Fe impurities was measured in terms harmonic susceptibilities ${\mathrm{\ensuremath{\chi}}}_{\mathrm{n}}$=${\mathrm{\ensuremath{\chi}}}_{\mathrm{n}}^{\ensuremath{'}}$-i${\mathrm{\ensuremath{\chi}}}_{\mathrm{n}}^{\mathrm{\ensuremath{''}}}$ (n=1, 2, 3, 5, and 7). results were analyzed the framework critical-state model weak-link model. Generation higher-harmonic seems to...
Angle-resolved photoemission from epitaxially grown $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}x}(001)$ single-crystal thin films reveals a clear Fermi edge and fine structure near the edge. Some of valence-band features show $k$-space dispersion. These new results suggest that electronic this oxide can be treated within framework one-electron band picture.
Superconducting Nd-Ce-Cu-O thin films were epitaxially grown on SrTiO3 (100) by activated reactive evaporation. As-grown showed the metallic temperature dependence of resistivity and superconducting transition at 12.5 K (R=0). The remarkable parallel shift onset resistive in magnetic fields was observed. Ginzburg–Landau coherence lengths along c axis basal plane are 7 96 Å, respectively.
We observe periodic oscillations in the weak magnetic-field magnetoresistance for quantum wires subjected to a corrugated gate. This enhanced is attributed backscattering of electrons from gate corrugations due direct ballistic trajectories through multiple (open) dot structures. Simulations transport also show evidence magnetoresistance, suggesting that classical are carried into behavior wire.
Tunneling spectra were observed in normal-metal--insulator--superconductor junctions fabricated from single-crystal films of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{x}}$(001), epitaxially grown on ${\mathrm{SrTiO}}_{3}$(100). The quasiparticle density states the perpendicular direction to Cu-O planes exhibits a lifetime broadening picture quasiparticles at gap edges. parameter increases with an increase temperature. recombination 60 K is...
Cu electroless plating is one of the most promising methods to form a seed layer electroplating for filling in TSV 3-D integration. However, with an increase aspect ratio TSV, uniformity thickness at sidewall becomes poor due consumption ions and reducing agents near entrance TSVs. In this study, we have studied addition PEG-thiol bath agent glyoxylic acid. We achieved conformal deposition diameters 4 10 μm by method. The remained constant depth even high This method very effective formation...
We present the latest results on searches for standard and beyond-the-standard model Higgs bosons in proton-antiproton collisions at [Formula: see text] by CDF DØ experiments Fermilab Tevatron. No significant excess is observed above expected background, cross section limits are calculated. It noticed that boson mass range 163 – 166 GeV/c 2 excluded 95% C.L.
Upgrade work towards increasing the beam intensity of neutrino production beamline at J-PARC is underway. Tertiary muon monitoring essential for stable operation beamline. Accordingly, we are planning to replace present monitor detectors with electron multiplier tubes (EMTs). We investigated linearity and radiation tolerance EMTs using a 90 MeV Research Center Electron Photon Science. show higher than Si sensors which presently used as one T2K long-baseline oscillation experiment J-PARC. The...
Abstract Upgrade work towards increasing the beam intensity of neutrino beamline at Japan Proton Accelerator Research Complex (J-PARC) is underway. Monitoring tertiary muon beams essential for stable operation beamline. Accordingly, we plan to replace present monitor sensors with electron multiplier tubes (EMTs). We investigated radiation tolerance and linearity response EMTs using a 90 MeV beam. were irradiated electrons up 470 nC. show higher than Si which are presently used as one...