A5028662742- Physics of Superconductivity and Magnetism
- Iron-based superconductors research
- Organic and Molecular Conductors Research
- Quantum and electron transport phenomena
- Diamond and Carbon-based Materials Research
- Corporate Taxation and Avoidance
- Rare-earth and actinide compounds
- Magnetism in coordination complexes
- Nuclear physics research studies
- Magnetic confinement fusion research
- Graphene research and applications
- Semiconductor materials and devices
- Electronic and Structural Properties of Oxides
- Ionosphere and magnetosphere dynamics
- Nuclear Physics and Applications
- Carbon Nanotubes in Composites
- Atomic and Subatomic Physics Research
- Magnetic and transport properties of perovskites and related materials
- Quantum Chromodynamics and Particle Interactions
- Inorganic Chemistry and Materials
- Advanced Condensed Matter Physics
- Magnetic properties of thin films
- Intellectual Capital and Performance Analysis
- Cold Atom Physics and Bose-Einstein Condensates
- Particle physics theoretical and experimental studies
National Institute for Materials Science
2014-2024
University of Tsukuba
2008-2024
Suzuka University of Medical Science
2021
Saitama University
2005-2018
Osaka University
1996-2018
The University of Tokyo
1997-2016
University of Manitoba
2016
Agriculture and Agri-Food Canada
2016
Hokkaido University
2016
Ehime University
2016
A huge enhancement of the superconducting transition temperature Tc was observed in a tetragonal FeSe superconductor under high pressure. The onset as 27K at 1.48GPa and pressure coefficient showed an extremely value 9.1K∕GPa. upper critical field Hc2 estimated to be ∼72T 1.48GPa. Because Hc2, system can applied wire rods.
We have established a plot of the anion height dependence Tc for typical Fe-based superconductors. The appeared symmetric curve with peak around 1.38 A. Both data at ambient pressure and under high obeyed unique curve. This will be one key strategies both understanding mechanism superconductivity search new superconductors higher Tc.
We synthesized a superconducting system of FeTe1−xSx with PbO-type structure. It has the simplest crystal structure among iron-based superconductors. The transition temperature is about 10 K when x 0.2. upper critical field Bc2(0) was estimated to be ~70 T. coherent length calculated ~2.2 nm. Since composed nontoxic elements, this material candidate for applications that will further advance research on
We have investigated the effect of atomic substitutions in FeSe system, which exhibits simplest crystal structure among iron-based superconductors. An enhancement superconducting transition temperature Tc was observed with substitution S or Te for Se; increased by up to 20 %, and also 75 %. In contrast, Co Ni Fe site significantly suppressed superconductivity. this work we present a detailed description technique employed determine system.
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.
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.
Under special conditions, a superconducting state where the order parameter oscillates in real space, so-called FFLO state, is theoretically predicted to exist near upper critical field, as first proposed by Fulde and Ferrell, Larkin Ovchinnikov. We report systematic measurements of interlayer resistance high magnetic fields 45 T two-dimensional magnetic-field-induced organic superconductor $\ensuremath{\lambda}\mathrm{\text{\ensuremath{-}}}(\mathrm{BETS}{)}_{2}{\mathrm{FeCl}}_{4}$, BETS...
We have fabricated the Fe(Se,Te) superconducting wire by a special process based on powder-in-tube method. The pure Fe tube plays role of not only sheath but also raw material for synthesizing phases. succeeded in observing zero resistivity current current–voltage measurements wire. Introduction pinning centers and fabricating multi-core will enhance critical density next step.
We synthesized the new Fe-based superconductor K0.8Fe2Se2 single crystals. The obtained crystal exhibited a sharp superconducting transition and onset zero-resistivity tempera-ture were estimated to be 33 31.8 K, respectively. A high upper critical field of 192 T was obtained. anisotropy superconductivity ∼3.6. Both comparably low are advantageous for applications under magnetic field.
Diamond is a wide bandgap semiconductor that can work at high temperatures and resist very electric fields. It endures harsh environments through its physical stability conducts heat well. These properties make diamond suitable for the fabrication of unique electronic devices. In particular, field effect transistors (FETs) have promising applications, including high-power converters trains vehicles high-frequency amplifiers telecommunications radar. Although mobility desirable these it has...
During thunderstorms on 20 September 2008, a simultaneous detection of $\ensuremath{\gamma}$ rays and electrons was made at mountain observatory in Japan located 2770 m above sea level. Both emissions, lasting 90 sec, were associated with thunderclouds rather than lightning. The photon spectrum, extending to 10 MeV, can be interpreted as consisting bremsstrahlung arriving from source which is 60--130 distance 90% confidence observed are likely dominated by primary population escaping an...
The critical concentration of superconductor-to-insulator transition in boron-doped diamond is determined two ways, namely, the actual doping boron and Hall carrier concentration. concentrations (111) (001) films exceed owing to distortion Fermi surface. high (110) effect interstitial atoms. A $3\ifmmode\times\else\texttimes\fi{}{10}^{20}\text{ }{\text{cm}}^{\ensuremath{-}3}$ substitutional site required for inducing superconductivity diamond.
We used the double sucrose gap apparatus to describe properties of electromechanical coupling in canine trachealis muscle, during infusion elevated K+ and 5-hydroxytryptamine (5-HT). With 59 mM 5-HT, quasi-steady-state relationships membrane depolarization tension indicate coupling, but for a given increase much smaller depolarizations were seen with 5-HT than K+. Evoked displacements potential anodal or cathodal current caused relaxations contractions, respectively, graded resulted changes....
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...
Diamond field-effect transistors (FETs) have potential applications in power electronics and high-output high-frequency amplifications. In such applications, high charge-carrier mobility is desirable for a reduced loss high-speed operation. We recently fabricated diamond FETs with hexagonal-boron-nitride gate dielectric observed above 300 cm$^{2}$V$^{-1}$s$^{-1}$. this study, we examine which scattering mechanism limits the of our through theoretical calculations. Our calculations reveal...
Moisture-induced superconductivity was observed in ${\text{FeTe}}_{0.8}{\text{S}}_{0.2}$. With exposing the sample to air, zero-resistivity temperature and superconducting volume fraction were enhanced up 7.2 K 48.5%, respectively, while as-grown showed only filamentary superconductivity. We concluded that causes of evolution water-related ions and/or molecules because kept water at room for several days The speed strongly by immersing into hot water.
We found that hot alcoholic beverages were effective in inducing superconductivity FeTe 0.8 S 0.2 .Heating compound various enhances the superconducting properties compared to pure water-ethanol mixture as a control.Heating with red wine for 24 hours leads largest shielding volume fraction of 62.4 % and highest zero resistivity temperature 7.8 K. Some components present beverages, other than water ethanol, have ability induce compound.
We report the successful fabrication of mono- and seven-core superconducting wires FeSe1-xTex using an in-situ Fe-diffusion process based on powder-in-tube (Fe-diffusion PIT) method. The reacted layer in these were found to have composite structure with composition nearly FeSe FeTe for inner outer layers, although a single FeSe0.5Te0.5 was supposed be formed. self-field transport Jc values at 4.2 K 226.2 A/cm2 100.3 respectively wires. Jc's dropped rapidly low fields then showed gradual...
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...
We report successful fabrication of multi- and mono-core FeSe wires with high transport critical current density Jc using a simple in-situ Fe-diffusion process based on the powder-in-tube (Fe-diffusion PIT) method. The seven-core wire showed as 1027 A/cm2 at 4.2 K. superconducting transition temperature Tczero was observed 10.5 K in wire-samples, which is about 2 higher than that bulk FeSe. PIT method suitable for fabricating multi-core binary superconductors superior properties.
Single crystals of La(O,F)BiSSe were grown by using a CsCl flux method. crystal X-ray structural analysis reveals that the structure is isostructural to BiS2- or BiSe2-based compounds crystallizing with space group P4/nmm (lattice parameters = 4.1110(2) Å, c 13.6010(7) Å). However, S atoms are selectively occupied at apical site Bi-SSe pyramids in superconducting layer. The single show transition around 4.2 K magnetic susceptibility and resistivity measurements. anisotropic parameter...
Pre beta 1-HDL promotes cholesterol efflux from cell membranes. Its plasma concentration is regulated by lecithin: acyltransferase (LCAT). To clarify whether the of pre changes in coronary artery disease (CAD), we determined distribution apolipoprotein A-I (apoA-I) among HDL subfractions 20 CAD patients and healthy controls, using nondenaturing two-dimensional gel electrophoresis. We found that had significantly higher concentrations than controls [7.6% +/- 3.4% vs 4.6% 2.3% apoA-I (P <...