A5048421926- Magnetic and transport properties of perovskites and related materials
- Advanced Condensed Matter Physics
- Multiferroics and related materials
- Aerodynamics and Fluid Dynamics Research
- Electronic and Structural Properties of Oxides
- Railway Engineering and Dynamics
- Rare-earth and actinide compounds
- Organic and Molecular Conductors Research
- Ferroelectric and Piezoelectric Materials
- Physics of Superconductivity and Magnetism
- X-ray Diffraction in Crystallography
- Magnetic Properties and Synthesis of Ferrites
- Railway Systems and Energy Efficiency
- Magnetism in coordination complexes
- Magnetic Properties of Alloys
- Engineering Applied Research
- Vehicle Noise and Vibration Control
- Magnetic properties of thin films
- Iron-based superconductors research
- Boron and Carbon Nanomaterials Research
- High-pressure geophysics and materials
- Wind and Air Flow Studies
- Molecular Junctions and Nanostructures
- Crystallization and Solubility Studies
- Aerodynamics and Acoustics in Jet Flows
Tohoku University
2000-2025
East Japan Railway (Japan)
2009-2024
Tokyo Institute of Technology
2020-2022
Saitama Prefecture
2022
Osaka University
2010-2019
Murata (Japan)
2016
Osaka Prefecture University
2016
SPring-8
2016
Nagoya Institute of Technology
2011
High Energy Accelerator Research Organization
2000-2009
The spatial charge arrangement of a typical quasi-two-dimensional organic conductor α-(BEDT-TTF) 2 I 3 is revealed by single crystal structure analysis using synchrotron radiation. results show that the horizontal-stripe-type structure, which was suggested mean field theory, established. We also find disproportionation above metal–insulator transition temperature and significant change in transfer integrals caused phase transition. Our result elucidates insulating this material as k F...
The origin of a room-temperature magnetoelectric (ME) effect has been examined by means neutron powder diffraction measurements for Z-type hexaferrite Sr(3)Co(2)Fe(24)O(41). temperature and magnetic-field dependence the electric polarization P several magnetic Bragg reflections show that commensurate order with (0,0,1) propagation vector an intimate connection ME effect. can be understood in terms appearance which is induced transverse conical spin structure through inverse...
Antiferroquadrupolar (AFQ) ordering has been conjectured in several rare-earth compounds to explain their anomalous magnetic properties. No direct evidence for AFQ ordering, however, reported. Using the resonant x-ray scattering technique near Dy L(III) absorption edge, we have succeeded observing order parameter DyB2C2 and analyzing energy polarization dependence. The much weaker coupling between orbital degrees of freedom lattice 4f electron systems than 3d makes them an ideal platform...
We report on structural, magnetic, and magnetoelectric (ME) properties of a U-type hexaferrite Sr4Co2Fe36O60 prepared by solid state reaction. Samples sintered at 1150–1180 °C in oxygen contain the fewest impurity phases show highly insulating behavior. Powder neutron diffraction results reveal that commensurate magnetic order with (0,0,3/2) propagation vector develops below TN2∼350 K. Corresponding to appearance order, sample shows small ME effect. These suggest is room-temperature material...
Under zero magnetic field, a quadrupolar order parameter at \(\mbi{q}_{Q}=(\frac{1}{2},\frac{1}{2},\frac{1}{2})\) in typical antiferro-quadrupole (AFQ) ordering compound CeB 6 has been observed for the first time by means of resonant X-ray scattering (RXS) technique. The RXS is 2 p →5 d dipole transition energy Ce L 3 -edge. Using this technique to observe pure AFQ state, phase diagram Phase II determined.
Synchrotron x-ray-diffraction experiments have been carried out in a perovskite-type vanadium oxide ${\mathrm{YVO}}_{3}$ to elucidate orbital ordering of the system. The change from C- G-type at lower magnetic transition temperature was strongly suggested. long-range appears also high-temperature paramagnetic phase. Azimuthal-angle dependence superlattice reflections indicates that for both orbital-ordering phases occupation is approximately ${d}_{\mathrm{xy}}^{1}{d}_{\mathrm{yz}}^{1}$ and...
In order to clarify its electric double layer (EDL) structure under external voltage, an interface between the ionic liquid N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide and a Au (111) surface was studied by x-ray reflectometry. A clear change in reflectivity observed as function of applied voltage. The electron density profile around calculated using models. Switching field reversed polarity EDL, magnitude voltage controlled layering well molecular...
Using a surface x-ray diffraction technique, we investigated the atomic structure of two types interfaces between LaAlO3 and SrTiO3, that is, p-type (SrO/AlO2) n-type (TiO2/LaO) interfaces. Our results demonstrate SrTiO3 in sample with interface has large polarized region, while limited region. In addition, intermixing was observed to extend deeper into substrate at compared p type. These differences result distinct degrees band bending, which likely contributes striking contrast electrical...
Cation distribution in transition-metal oxides is closely tied to their physical properties. Here we employed resonant x-ray-diffraction technique and quantitatively evaluated the cation inverse spinel $\mathrm{NiC}{\mathrm{o}}_{2}{\mathrm{O}}_{4}$ films that were epitaxially grown by pulsed laser deposition. Our results reveal oxygen partial pressure during growth ${P}_{\mathrm{O}2}$ a key parameter determining films, with larger leading an increase Ni concentration occupying octahedral...
A study of resonant-x-ray scattering in a charge-ordered perovskite manganese oxide ${\mathrm{Nd}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}$ was performed. Dipole-resonant superlattice reflections originating from the orderings charge and orbital with ${Q}_{\mathrm{charge}}=(0,1,0)$ ${Q}_{\mathrm{orbital}}=(0,1/2,0)$ $\mathrm{Pbnm}$ setting were observed. Sudden change intensity at transition temperature indicated strong first-order phase transition. Characteristic dependence on x-ray...
We studied the magnetic and magnetoelectric properties of Ba2-xSrxNi2Fe12O22 single crystals over a wide composition range (0 ≤ x 1.5). All show ferrimagnetic order at around 660 K. While Sr-free crystal is simply down to lowest temperature, transition from into screw ordered state was observed temperatures below 300 K in Sr-substituted crystals. The temperature monotonically increases with increasing Sr content, meaning that stabilized by Sr-substitution. By applying field perpendicular...
The orbitally ordered state of ${\mathrm{YTiO}}_{3}$ has been investigated utilizing resonant x-ray scattering (RXS) near the Ti K-edge. RXS intensities have observed at $1\stackrel{\ensuremath{\rightarrow}}{s}4p$ dipole transition energy (the main edge). atomic tensor ion quantitatively determined by measurements azimuthal angle and polarization dependence signal several vectors. On basis tensor, we discuss not only mechanism but also wave function state, finding it to be a linear...
A novel structure of orbital ordering is found in a Nd0.5Sr0.5MnO3 thin film, which exhibits clear first-order transition, by synchrotron x-ray diffraction measurements. Lattice parameters vary drastically at the metal-insulator transition 170 K (= T(MI)), and superlattice reflections appear below 140 T(CO)). The electronic between T(MI) T(CO) identified as A-type antiferromagnetic with d(x2-y2) ferro-orbital ordering. new type antiferro-orbital characterized wave vector (1/4 1/4 1/2) cubic...
The electrical resistivity and X-ray oscillation photograph measurements for an MMX-chain complex, Pt2(dtp)4I (dtp = C2H5CS2-), under high pressure were performed. We observed the most stable metallic phase (TMI 70 K, 2.2 GPa) in 1-D purely d-electronic conductors pressure-induced metal-insulator transition including structural at 3.0 GPa.
We investigated magnetostrictive properties of a triangular lattice antiferromagnet CuCrO 2 showing an incommensurate proper-screw spin order by means x-ray diffraction and strain gauge measurements. A deformation the plane leading to lowered crystallographic symmetry was found upon magnetic ordering, which demonstrates strong spin–lattice coupling in this system. The resultant multiple structural domains can be successfully arranged field cooling procedures. discuss relationship between...
Magnetocapacitive effects were investigated for N\'eel's $N$-type ferrimagnetic ${\text{SmMnO}}_{3}$, which shows temperature-induced magnetization reversal at the compensation temperature $({T}_{\text{comp}}=9.4\text{ }\text{K})$ in a low magnetic field $B$ $(<\ensuremath{\sim}1\text{ }\text{T})$. When higher is applied, remarkable anomalies observed profiles of magnetization, dielectric constant, and relaxation time around ${T}_{\text{comp}}$. These coupled field-induced give rise to...
Ultrafast photoinduced transitions of a one-dimensional Mott insulator into two distinct electronic phases, metal and charge-density-wave (CDW) state, were achieved in bromine-bridged Pd-chain compound [$\mathrm{Pd}{(\mathrm{en})}_{2}\mathrm{Br}]{({\mathrm{C}}_{5}\text{\ensuremath{-}}\mathrm{Y})}_{2}{\mathrm{H}}_{2}\mathrm{O}$ ($\mathrm{en}=\text{ethylenediamine}$ ${\mathrm{C}}_{5}\text{\ensuremath{-}}\mathrm{Y}=\text{dialkylsulfosuccinate}$), by selecting the photon energy femtosecond...
Significance The quantum spin liquid state has been intensively pursued since Anderson proposed the resonating valence bond model. On other hand, liquids based on another electronic degree of freedom, orbital, believed unrealistic, because energy scale orbital correlation is normally one order magnitude higher than exchange coupling, resulting in an ordering at a signicantly high temperature accompanied by cooperative Jahn−Teller (JT) distortion. In this paper, we present striking complete...
The "devil's staircase"-type phase transition in the quarter-filled spin-ladder compound NaV2O5 has been discovered at low temperature and high pressure by synchrotron radiation x-ray diffraction. A large number of transitions are found to successively take place among higher-order commensurate phases with 2a x 2b zc type superstructures. observed dependence modulation wave q(c), defined 1/z, is well reproduced axial next nearest neighbor Ising model. q(c) suggested reflect atomic...
We report the structural characterization and transport properties of highly-ordered epitaxial γ-Fe 2 O 3 thin films grown by a pure ozone-assisted molecular beam epitaxy method. X ray diffraction (XRD) measurements at synchrotron facility indicated that composition was close to with Fe vacancy only occurring octahedral sites spinel. revealed crystal symmetry reduced from cubic, giving rise extra superlattice reflections along c * axis this showed good agreement tetragonal structure...
Abstract Time-resolved X-ray magnetic circular dichroism under the effects of ferromagnetic resonance (FMR), known as (XFMR) measurements, enables direct detection precession dynamics moment. Here we demonstrated XFMR measurements and Bayesian analyses a quantitative probe for spin orbital moments FMR effect. Magnetization precessions in two different Pt/Ni-Fe thin film samples were directly detected. Furthermore, ratio dynamical was evaluated quantitatively by energy spectra around Ni...