A5059898779- Magnetic and transport properties of perovskites and related materials
- Physics of Superconductivity and Magnetism
- Magnetic properties of thin films
- Advanced Condensed Matter Physics
- Heusler alloys: electronic and magnetic properties
- Multiferroics and related materials
- Electronic and Structural Properties of Oxides
- Rare-earth and actinide compounds
- Quantum Chromodynamics and Particle Interactions
- Magnetic Properties and Applications
- Diamond and Carbon-based Materials Research
- ZnO doping and properties
- Metal and Thin Film Mechanics
- Particle physics theoretical and experimental studies
- Thermal Expansion and Ionic Conductivity
- Ferroelectric and Piezoelectric Materials
- Particle accelerators and beam dynamics
- Magnetic Properties of Alloys
- Superconductivity in MgB2 and Alloys
- Superconducting Materials and Applications
- MXene and MAX Phase Materials
- High-Energy Particle Collisions Research
- Acoustic Wave Resonator Technologies
- Magnetic Properties and Synthesis of Ferrites
- Photonic and Optical Devices
Nagoya University
2015-2025
Nagoya Industrial Science Research Institute
2016-2023
RIKEN BNL Research Center
2017-2019
Nara Women's University
2018-2019
Centre National de la Recherche Scientifique
2018
Institut National de Physique Nucléaire et de Physique des Particules
2018
Far Eastern Federal University
2018
Université Paris-Sud
2018
Brookhaven National Laboratory
2017
University of Connecticut
2017
We attempted to fabricate a high-quality Fe3O4 film while satisfying both low-thermal preparation (≦573 K) and thinness (≦500 Å). X-ray diffractometry showed that our prepared was epitaxially grown onto MgO (100) substrate. The saturation magnetization, resistivity, Verwey point were, respectively, ∼438 emu/cm3, ∼10 000 μ Ω cm, ∼110 K. These values were comparable those of the bulk. Our experimental results suggested could be obtained even under crucial conditions deposition temperature...
We calculate the nucleon sigma term in two-flavor lattice QCD utilizing Feynman-Hellman theorem. Both sea and valence quarks are described by overlap fermion formulation, which preserves exact chiral flavor symmetries on lattice. analyze data for mass using analytical formulae derived from baryon perturbation theory. From at quark set different mass, we may extract contribution to term, corresponds strange content. find that content is much smaller than previous calculations phenomenological...
We calculate the scalar and tensor charges of nucleon in 2+1-flavor lattice QCD, for which systematics renormalization disconnected diagram is well controlled. Numerical simulations are performed at a single spacing = 0.11 fm. simulate four pion masses, cover range $m_\pi \sim$ 290 - 540 MeV, strange quark mass close to its physical value. The statistical accuracy improved by employing so-called low-mode averaging technique truncated solver method. study up, down, contributions calculating...
We calculate the strange quark content of nucleon $⟨N|\overline{s}s|N⟩$ in $2+1$ -flavor lattice QCD. Chirally symmetric overlap fermion formulation is used to avoid contamination from up and down contents due an operator mixing between light scalar operators, $\overline{s}s$ $\overline{u}u+\overline{d}d$. At a spacing $a=0.112(1)\text{ }\text{ }\mathrm{fm}$, we perform calculations at four values degenerate masses ${m}_{ud}$, which cover range pion mass...
The authors reexamine the form of expression used to extract nucleon EDM from lattice QCD calculations and discover a subtle additional subtraction due mixing between factors. They check their claim by comparing with different method compute EDM. Applying correction previous computations they obtain more consistent results, albeit now all vanishing within errors.
Bulk samples of La2−2xCa1+2xMn2O7 with the layered Sr3Ti2O7-type perovskite structure have been successfully synthesized and investigated respect to their magnetic electrical properties. It is found that (x=0.25) a metallic ferromagnet transition temperature Tc 215 K. The large magnetoresistance (MR) effect Δρ/ρ0 ∼60% at 1.8 T was observed in wide range below cusp resistivity 96 K, which well Tc. This behavior quite different from well-known double-exchange ferromagnets such as La1−xCaxMnO3,...
The resistivity and magnetization of layered perovskite ${\mathrm{La}}_{2\ensuremath{-}2x}{\mathrm{Ca}}_{1+2x}{\mathrm{Mn}}_{2}{\mathrm{O}}_{7}$ have been studied systematically using bulk samples with a wide doping concentration range $0<~x<~0.5$ epitaxial thin film $x=0.3.$ system becomes metallic ferromagnet for concentrations $0.22<~x<~0.5.$ In this region, results as well films clearly shown that there are two types ferromagnetic ordering, possibly originating from an...
A spin-polarized electron beam has been used as the probe in a transmission microscope by using photocathode gun with made of GaAs–GaAsP strained superlattice semiconductor negative affinity (NEA) surface. This system had spatial resolution order 1 nm for at 30 keV and it can generate an energy width 0.24 eV without employing monochromators. narrow suggests that NEA realize high energy-loss spectroscopy longitudinal coherence 3 × 10−7 m.
We report electrical current switching of noncollinear antiferromagnetic (AFM) Mn$_3$GaN/Pt bilayers at room temperature. The Hall resistance these can be manipulated by applying a pulse $1.5\times10^6$~A/cm$^2$, whereas no significant change is observed up to $\sim10^8$~A/cm$^2$ in Mn$_3$GaN single films, indicating that the Pt layer plays an important role. In comparison with ferrimagnetic bilayers, lower AFM demonstrated, critical density two orders magnitude smaller. Our results...
Epitaxial thin films of ordered double-perovskite Sr2FeMoO6−y are deposited on (001) SrTiO3 substrates by pulsed-laser deposition using a two step growth process. Selection conditions is found to lead either highly conductive metallic (residual resistivity about 1 μΩ cm) or semiconducting films. The show positive magnetoresistance (MR) as high 35%, while the negative MR −3%, at temperature 5 K and field 8 T.
Superconducting films of Eu 1 Ba 2 Cu 3 O 7- y have been grown in situ onto SrTiO and MgO (100) substrates by magnetron sputtering from a stoichiometric oxide target. The process results the growth epitaxial with perfect -axis orientation as well c orientation. can be controlled proper choices substrate temperature, oxygen pressure, film rate. routine production showing T zero 88–90 K is accomplished. In particular importance fabrication multilayer structures such tunnel junctions.
Y-Ba-Cu-O thin films have been prepared on sapphire substrates by RF magnetron sputtering from sintered targets. The substrate temperature dependence of Ba and Cu concentrations against Y as-sputtered has clarified. Film composition deviated target composition. concentration decreased significantly with increasing T s , while was independent the temperature. Using CuO-compensated 1 6 10 O x target, assputtered high- c ( onset=87 K, endpoint=40 K) successfully obtained as a about 580°C.
The brightness and interference fringes of a spin-polarized electron beam extracted from semiconductor photocathode excited by laser irradiation are directly measured via its use in transmission microscope. was 3.8 × 107 A cm−2 sr−1 for 30-keV energy with the polarization 82%, which corresponds to 3.1 108 200-keV energy. resulting exhibited long coherence length at specimen position due high parallelism (1.7 ± 0.3) 10−5 rad, generated representative first-order correlation using an biprism....
Precise crystal structure analysis by neutron powder diffraction is performed for rare-earth orthoniobates (RNbO4: R = La, Nd, Ho and Yb) the distortion of NbO4 tetrahedra estimated with normal-coordinate method. Displacement cubic symmetry mode large increases decreasing ionic radius VIIIR3+. This displacement produces a regular tetrahedron NbO4. The mean value Nb–O distances in RNbO4 crystals 1.834 Å. nearly equal to bond length s 5/4, \overline 1.828 Å, bond-valence Displacements other...
Thin films of ordered double-perovskite Sr2CrReO6 have been grown epitaxially onto SrTiO3 substrates by sputtering, and their microstructural, electrical, magnetic properties are investigated. It is found that a wide growth-temperature range at least 700–800°C can yield epitaxial with superior atomically flat surfaces. These exhibit Curie temperatures Tc up to 620K, saturation magnetizations Ms 0.9μB∕formula unit (f.u.), which comparable the predicted value 1μB∕f.u. for fully half-metallic...
The space charge effect has been clearly observed in the energy distributions of picosecond pulse beams from a spin-polarized electron microscope, and was found to depend upon quantity per pulse. non-linear phenomena associated with this have also replicated beam simulations that take into account three-dimensional charge. results show 500 aC/pulse provides highest brightness 16-ps duration, 30-keV energy, an emission spot 1.8 μm. Furthermore, degeneracy wave packet pulsed evaluated be 1.6 ×...
We report the anomalous Hall effect (AHE) in antiperovskite Mn$_{3}$NiN with substantial doping of Cu on Ni site (i.e. Mn$_{3}$Ni$_{1-x}$Cu$_{x}$N), which stabilizes a noncollinear antiferromagnetic (AFM) order compatible AHE. Observed both sintered polycrystalline pieces and single crystalline films, AHE does not scale net magnetization, contrary to conventional ferromagnetic case. The existence is explained through symmetry analysis based $\Gamma_{\rm 4g}$ AFM doped Mn$_{3}$NiN. DFT...
The effects of photoinduced hole doping, caused by persistent photoconductivity, on the normal and superconducting properties ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{\mathit{y}}$ (6.35\ensuremath{\le}y\ensuremath{\le}6.70) thin films are studied using a high-power-density He-Ne laser light. Substantial enhancements both conductivity ${\mathit{T}}_{\mathit{c}}$ found for all films. Hall measurements reveal that number holes depends only photon dose is independent oxygen content....
We report strong spin-orbit torques (SOTs) generated by noncollinear antiferromagnets Mn3Ni0.35Cu0.65N, over a wide temperature range. The SOT efficiency peaks up to 0.3 at the Néel (TN), substantially higher than that of commonly studied nonmagnets, such as Pt. sign and magnitude SOTs measured in our experiments are corroborated density functional theory, confirming dominance orbital Hall effect spin nonmagnetic phase above TN. In contrast, temperature-dependent observed around below TN can...