A5101728310- Iron-based superconductors research
- Rare-earth and actinide compounds
- Physics of Superconductivity and Magnetism
- Corporate Taxation and Avoidance
- Diamond and Carbon-based Materials Research
- Magnetic Properties of Alloys
- Semiconductor materials and devices
- Graphene research and applications
- Semiconductor materials and interfaces
- Superconductivity in MgB2 and Alloys
- Intellectual Capital and Performance Analysis
- Electronic and Structural Properties of Oxides
- GaN-based semiconductor devices and materials
- Magnetic Properties and Applications
- Radio Frequency Integrated Circuit Design
- Electron and X-Ray Spectroscopy Techniques
- Silicon Nanostructures and Photoluminescence
- Magnetic properties of thin films
- Metal and Thin Film Mechanics
- Advanced Condensed Matter Physics
- Inorganic Chemistry and Materials
- Magnetic and transport properties of perovskites and related materials
- Advanced Materials Characterization Techniques
- Surface and Thin Film Phenomena
- Catalytic Processes in Materials Science
National Institutes for Quantum Science and Technology
2020-2024
National Institute for Materials Science
2011-2020
Japan Synchrotron Radiation Research Institute
2016-2020
SPring-8
2018-2020
Okayama University
2006-2019
Mitsubishi Electric (Japan)
2016-2018
Hyogo University
2016
Mitsubishi Electric (United States)
2016
Okayama University of Science
2007-2014
Japan Science and Technology Agency
2009-2012
We have successfully synthesized the new BiS2-based superconductor NdOBiS2 by F doping. This compound is composed of superconducting BiS2 layers and blocking NdO layers, which indicates that layer analogous to CuO2 in cuprates or Fe–As Fe-based superconductors. can obtain NdO1-xFxBiS2 with bulk superconductivity a solid-state reaction. Therefore, should be suitable material for elucidating mechanism layer.
Hepatocyte growth factor (HGF), a mesenchymal-derived which regulates growth, motility, and morphogenesis of epithelial endothelial cells, functions as hepatotrophic renotrophic for regeneration the liver kidney. We have now obtained evidence that transforming factor-beta 1 (TGF-beta 1) glucocorticoids are negative regulators HGF gene expression. When TGF-beta or dexamethasone was added to cultures MRC-5 human embryonic lung fibroblasts HL-60 promyelocytic leukemic amount secreted into...
Novel BiS2-based superconductors LaO1-xFxBiS2 prepared by the high pressure synthesis technique were systematically studied. It was found that annealing strongly lattice as compared to samples conventional solid state reaction at ambient pressure. Bulk superconductivity observed within a wide F-concentration range of x = 0.2 ~ 0.7. On basis those results, we have established phase diagram LaO1-xFxBiS2.
The phase diagram of SmFeAsO1−xFx in terms x is exhibited this study. Specimens from = 0 to 0.3 were prepared by low-temperature sintering with slow cooling. suppresses the formation amorphous FeAs, which inevitably produced as an impurity when using high-temperature sintering. Moreover, cooling effective obtaining a high fluorine concentration. compositional change feedstock composition quite small after synthesis. We can reproducibly observe record superconducting transition for iron-based...
We have observed zero resistivity above 10 K and an onset of reduction at 25.2 in a heavily B-doped diamond film. However, the effective carrier concentration is similar to that superconducting with lower Tc. found has longer mean free path lifetime than previous report, indicating this highest Tc better crystallinity compared other films. In addition, susceptibility shows small transition 20 high quality diamond, suggesting signature superconductivity K. These results strongly suggest...
We show the observation of coexistence bulk superconductivity and magnetic ordering in CeO1−xFxBiS2 (x = 0–1.0) prepared by annealing under high pressure. In system, both two types ferromagnetic-like with transition temperatures 4.5 7.5 K are induced upon systematic F substitution. This fact suggests that carriers generated substitution O supplied to not only BiS2 superconducting layers but also CeO blocking layers. Furthermore, highest temperature is observed when increases, which implies...
In Nd-Fe-B sintered magnets, observations of how reversed magnetic domains propagate throughout the entire hysteresis loop have been restricted to polished surfaces or transmittable thin films. However, mechanical processing surface introduces defects that nucleate additional which mask underlying domain pattern. To unmask interior structure represents bulk, soft x-ray absorption microscopy is utilized in this paper track reversal individual grains and fractured surfaces. Significant...
We synthesized superconducting fullerene nanowhiskers (C60NWs) by potassium (K) intercalation. They showed large volume fractions, as high 80%. The transition temperature at 17 K was independent of the content (x) in range between 1.6 and 6.0 K-doped C60 (KxC60NWs), while fractions changed with x. highest shielding fraction a full observed material K3.3C60NW heating 200 °C. On other hand, that (K-C60) crystal less than 1%. report behaviors our newly KxC60NWs comparison to those KxC60...
For the purpose of imaging element- and shell-specific magnetic distributions under high fields, a scanning soft X-ray microscope has been developed at beamline BL25SU, SPring-8, Japan. The utilizes total electron yield detection absorbed circularly polarized X-rays in order to observe domains through circular dichroism effect. Crucially, this system is equipped with an 8 T superconducting magnet. performance features present are demonstrated by domain observations fractured surface Nd 14.0...
We use photoemission spectroscopy to study electronic structures of pristine and K-doped solid picene. The valence band spectrum picene consists three main features with no state at the Fermi level $({E}_{\text{F}})$ while that has similar those new states near ${E}_{\text{F}}$, consistent semiconductor-metal transition. K-induced change cannot be explained a simple rigid-band model but can interpreted by molecular-orbital calculations considering electron-intramolecular-vibration...
The electronic structure of nearly optimally-doped novel superconductor LaO$_{1-x}$F$_x$BiS$_2$ (${\it x}$ = 0.46) was investigated using angle-resolved photoemission spectroscopy (ARPES). We clearly observed band dispersions from 2 to 6 eV binding energy and near the Fermi level E}_{\rm F}$), which are well reproduced by first principles calculations when spin-orbit coupling is taken into account. ARPES intensity map ${\it F}$ shows a square-like distribution around $\Gamma$(Z) point in...
Shubnikov--de Haas oscillations are observed in atomically flat hydrogen-terminated diamond surfaces with high-density hole carriers introduced by the electric field effect using an ionic liquid. The depend only on magnetic component perpendicular to surface, thus providing evidence of two-dimensional Fermi surfaces. effective masses estimated from temperature dependence close cyclotron valence band maxima diamond. quantum scattering time is one order magnitude longer than transport and...
Low voltage operation of picene thin film field-effect transistor (FET) has been realized with 40 nm thick SiO2 gate dielectrics coated by two polymers, Cytop™ and polystyrene. The FETs operated in low absolute |VG| below 15 V for 30 polystyrene dielectrics, they showed a significant O2 gas sensing effect down to ∼10 ppm. Photoemission spectrum clarified that molecules penetrate into the films at O2/picene mole ratio 1: 1. X-ray diffraction pattern highly oriented growth on polymer-coated SiO2.
We have established a simple process that allows for the one-step synthesis of KxFe2−ySe2 single crystals, which exhibit high critical current density Jc. The post annealing and quenching technique has improved homogeneity as-grown resulting in full shielding external magnetic field. quenched crystals show superconducting transition at Tconset=32.9 K Tczero=32.1 K. upper fields μ 0 H02 (0) H||ab H||c are estimated to be ∼206 ∼50 T, respectively. densities Jc reach as 1.0×105 3.4×104 A/cm2 5...
The magnetocapacitance effect was investigated using impedance spectroscopy on single crystals of ${\mathrm{LuFe}}_{2}{\mathrm{O}}_{4}$. intrinsic response could be separated from the interfacial and showed a clear hysteresis loop below ${T}_{\mathrm{Ferri}}\ensuremath{\sim}240\text{ }\text{ }\mathrm{K}$ under magnetic field. neutron diffraction experiment field proves origin dielectric property related to motion nanosized ferromagnetic domain boundary. These results imply that modification...
We use core level and valence band soft x-ray photoemission spectroscopy (SXPES) to investigate electronic structure of new BiS$_{2}$ layered superconductor LaO$_{1-x}$F$_{x}$BiS$_{2}$. Core spectra doped samples show a spectral feature at the lower binding energy side Bi 4${f}$ main peak, which may be explained by core-hole screening with metallic states near Fermi ($E_{\rm F}$). Experimental its ${x}$ dependence (higher shift as well appearance $E_{\rm F}$ having dominant 6${p}$ character)...
Abstract Iron-based 1111-type superconductors display high critical temperatures and relatively current densities J c . The typical approach to increasing is introduce defects control dissipative vortex motion. However, when optimized, this theoretically predicted be limited achieving a maximum of only ∼30% the depairing density d , which depends on coherence length penetration depth. Here we dramatically boost in SmFeAsO 1– x H films using thermodynamic aimed at incorporating pinning...