A5023875457- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Magnetic properties of thin films
- Diamond and Carbon-based Materials Research
- Ion-surface interactions and analysis
- High-pressure geophysics and materials
- Magnetic Properties and Applications
- Multiferroics and related materials
- Magneto-Optical Properties and Applications
- Rare-earth and actinide compounds
- Quantum and electron transport phenomena
- Iron-based superconductors research
- Theoretical and Computational Physics
- Integrated Circuits and Semiconductor Failure Analysis
- Metal and Thin Film Mechanics
- Nuclear Physics and Applications
- Electronic and Structural Properties of Oxides
- Characterization and Applications of Magnetic Nanoparticles
- Atomic and Subatomic Physics Research
- Magnetic Properties and Synthesis of Ferrites
- ZnO doping and properties
- Semiconductor materials and devices
- Atomic and Molecular Physics
- Superconducting Materials and Applications
Gifu University
2016-2024
National Institutes for Quantum Science and Technology
2016-2024
Tokyo University of Agriculture and Technology
2024
University of Tokyo Hospital
2023
National Institute of Advanced Industrial Science and Technology
2023
Takasaki Advanced Radiation Research Institute
2013-2022
Teikyo University Chiba Medical Center
2022
Hyogo Prefectural Amagasaki General Medical Center
2022
Kyoto University
2005-2021
Kyoto University Institute for Chemical Research
2002-2021
Spintronics is one of the emerging fields for next-generation nanoelectronic devices to reduce their power consumption and increase memory processing capabilities. Such utilise spin degree freedom electrons and/or holes, which can also interact with orbital moments. In these devices, polarisation controlled either by magnetic layers used as spin-polarisers or analysers via spin–orbit coupling. Spin waves be carry current. this review, fundamental physics phenomena described first respect...
Systematic low-energy neutron-scattering studies have been performed on float-zone-grown single crystals of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ with $x$ extending from zero doping, $x=0$, to the overdoped, weakly superconducting regime, $x=0.25$. For beyond a critical doping value ${x}_{c}\ensuremath{\approx}0.05$ spin-fluctuation peak position shifts ($\frac{1}{2}$, $\frac{1}{2}$) ($\frac{1}{2}$\ifmmode\pm\else\textpm\fi{}\ensuremath{\delta},...
We report elastic, quasielastic (F dE), and inelastic neutron-scattering studies of the instantaneous dynamic spin fluctuations in as-grown doped ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$. Four samples have been studied: (A) ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$ with ${T}_{N}$=195 K, (B) oxygenated ${\mathit{T}}_{\mathit{N}}$\ensuremath{\simeq}100 (C) ${\mathrm{La}}_{2}$${\mathrm{Cu}}_{0.95}$${\mathrm{Li}}_{0.05}$${\mathrm{O}}_{4}$, (D)...
An (hk0)-oriented p-type CaFe2O4 (E(g): 1.9 eV) photocathode was prepared, and hydrogen oxygen gases were produced from a photocell short-circuited by connecting the n-type TiO2 electrodes under illumination without applying an external voltage. The open-circuited voltage 0.97 V short-circuit current about 200 μA/cm(2), amount of evaluated after 2 days reaction 70 4 μmol, respectively.
We present a neutron scattering study of stripe correlations measured on single crystal La$_{1.875}$Ba$_{0.125}$CuO$_{4}$. Within the low-temperature-tetragonal (LTT) phase, superlattice peaks indicative spin and charge order are observed below 50 K. For excitation energies $\hbar\omega\le12$ meV, we have characterized magnetic excitations that emerge from incommensurate peaks. In ordered state, these similar to waves. Following as function temperature, find there is relatively little change...
Using neutron-scattering techniques, we have studied the temperature dependence of magnetic excitations at varied energies in a high-quality single crystal ${\mathrm{La}}_{1.85}$${\mathrm{Sr}}_{0.15}$${\mathrm{CuO}}_{4}$. This exhibits sharp superconducting transition 33 K with nearly 100% flux exclusion. For excitation 9 meV and lower, intensity drops dramatically decreasing for temperatures below \ensuremath{\sim}150 K. However, 12 MeV is independent between 300 5
We report neutron-scattering measurements of spin-density wave order within the superconducting state a single crystal predominately stage-4 ${\mathrm{La}}_{2}{\mathrm{CuO}}_{4+y}$ with ${T}_{c}$ (onset) 42 K. The low-temperature elastic magnetic scattering is incommensurate lattice and characterized by long-range in copper-oxide plane spin direction identical to that insulator. Between neighboring planes, spins exhibit short-range correlations stacking arrangement reminiscent undoped...
The three-dimensional (3D) magnetism present in ${\mathrm{Nd}}_{2}$${\mathrm{CuO}}_{4}$ and ${\mathrm{Pr}}_{2}$${\mathrm{CuO}}_{4}$ has been examined neutron-scattering experiments. Antiferromagnetic long-range order of the ${\mathrm{Cu}}^{2+}$ moments develops below ${\mathit{T}}_{\mathit{N}}$=255 K both compounds. In a series magnetic phase transitions which spins reorient also observed ${\mathit{T}}_{\mathit{N}}$, while 3D spin structure is stable. No changes crystalline associated with...
We report on neutron scattering studies of the dynamic spin correlations in ${\mathrm{La}}_{2\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Sr}}_{\mathrm{x}}$${\mathrm{CuO}}_{4\mathrm{\ensuremath{-}}\mathrm{y}}$. Two superconducting and one nonsuperconducting single crystals were studied. All three samples exhibited metallic normal-state resistivity modified by corrections consistent with localization effects. The structure factor S(Q,\ensuremath{\omega}) measured these reflects to a first...
We report a neutron scattering study of the spin fluctuations in samples ${\mathrm{La}}_{1.89}$${\mathrm{Sr}}_{0.11}$Cu${\mathrm{O}}_{4}$ which are \ensuremath{\sim}80% superconducting with ${T}_{c}=10$ K. The structure factor $S(\mathrm{Q})$ reflects three-dimensional modulated correlations an in-plane correlation length order 18\ifmmode\pm\else\textpm\fi{}6 \AA{}. evolve temperature from being predominantly dynamic at high temperatures to mainly quasielastic ($|\ensuremath{\Delta}E|<0.5$...
T-linear term of specific heat and magnetic susceptibility at zero temperature are derived for the heavy electron systems, relations among these quantities discussed on basis Fermi liquid theory. Further, a rigorous expression T2-term resistivity low temperatures is also obtained Kubo formula. It shown that coefficient arising from interaction strongly enhanced though it vanishes because momentum conservation free system possessing no crystal lattice.
Magnetic superlattice peaks are observed in single-crystal neutron-diffraction measurements on orthorhombic ${\mathrm{La}}_{1.88}{\mathrm{Sr}}_{0.12}{\mathrm{CuO}}_{4}$ at reciprocal points of (1/2\ifmmode\pm\else\textpm\fi{}\ensuremath{\epsilon},1/2,0) and (1/2,1/2\ifmmode\pm\else\textpm\fi{}\ensuremath{\epsilon},0) the tetragonal notation where $\ensuremath{\epsilon}=$0.126$\ifmmode\pm\else\textpm\fi{}$0.003. The La NMR measurement reveals a broadening field-swept spectrum below...
We report elastic neutron diffraction and muon spin relaxation ( $\ensuremath{\mu}\mathrm{SR}$) measurements of the quasi-one-dimensional antiferromagnets ${\mathrm{Sr}}_{2}{\mathrm{CuO}}_{3}$ ${\mathrm{Ca}}_{2}{\mathrm{CuO}}_{3}$, which have extraordinarily reduced ${T}_{N}/J$ ratios. observe almost resolution-limited antiferromagnetic Bragg reflections in obtain a ordered moment size $\ensuremath{\sim}0.06{\ensuremath{\mu}}_{\mathrm{B}}$. find that ratio...
Neutron inelastic scattering experiments have been performed on homogeneous single crystals of ${\mathrm{La}}_{1.85}{\mathrm{Sr}}_{0.15}{\mathrm{CuO}}_{4}$ with ${T}_{c}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}37.3$ K (at onset), higher than any previously studied crystals. The temperature dependence the low energy incommensurate peak intensity at $(\ensuremath{\pi}(1\ifmmode\pm\else\textpm\fi{}\ensuremath{\delta}),\ensuremath{\pi})$ and...
Neutron-scattering experiments with markedly improved signal-to-noise ratios have been performed on single-crystal superconducting ${\mathrm{La}}_{1.85}$${\mathrm{Sr}}_{0.15}$${\mathrm{CuO}}_{4}$ (${\mathit{T}}_{\mathit{c}}$=33 K) at energies down to 1.5 meV. The measurements provide quantitative information the temperature dependence of \ensuremath{\chi}''(q,\ensuremath{\omega}). Surprisingly, \ensuremath{\chi}''(${\mathbf{q}}_{\mathrm{peak}}$,\ensuremath{\omega}) is approximately constant...
The dynamic spin susceptibility, $\chi''(\omega)$, has been measured over the energy range of $2 \leq \omega 10$ meV for overdoped La$_{2-x}$Sr$_{x}$CuO$_{4}$. Incommensurate (IC) excitations are observed at 8 K all superconducting samples $0.25 x 0.28$ with $\chi''$ peaking $\sim 6$ meV. IC peaks 6 become smaller in intensity increasing $x$ and, finally, unobservable a sample $x=0.30$ which no bulk superconductivity. maximum decreases linearly $T_c$(onset) region, implying direct...
Using large single crystals (\ensuremath{\sim}2 ${\mathrm{cm}}^{3}$), we have extended previous elastic and inelastic neutron scattering studies of the spin dynamics in two-dimensional (2D) quantum antiferromagnet ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$. We observe well-defined magnetic peaks for constant energy scans across 2D rod a wide range temperatures energies. The spectra are compared quantitatively with theoretical models. Simple spin-wave theory satisfactorily describes experimental...
We have observed successive magnetic phase transitions in a ${\mathrm{La}}_{2}$Co${\mathrm{O}}_{4}$ single crystal by neutron scattering measurements. Antiferromagnetic long-range order of the ${\mathrm{La}}_{2}$Ni${\mathrm{O}}_{4}$ type, $\ensuremath{\tau}[100]$, S[100], is with N\'eel temperature ${T}_{N}=275$ K orthorhombic (Cmca) phase. As lowered, first-order transition to new tetragonal found at ${T}_{2}\ensuremath{\sim}135$ K. This structural accompanied ${\mathrm{Co}}^{2+}$...
${\mathrm{Nd}}_{2}$${\mathrm{CuO}}_{4}$ is found to be a quasi-two-dimensional antiferromagnet with ${T}_{N}$=255 K. Successive phase transitions occur due the ${\mathrm{Cu}}^{2+}$ spin reorientation as well as, at low temperatures, participation of ${\mathrm{Nd}}^{3+}$ spins in three-dimensional long-range order. A sharp peak corresponding two-dimensional correlations observed energy-integrated scans. The magnetic properties high temperatures are closely similar those...
We report a time-resolved propagating spin wave spectroscopy for Fe19Ni81 film. show that the amplitude of spin-wave packet depends on direction magnetization and its phase can be controlled by polarity pulsed magnetic field excitation. The nonreciprocal emission utilized binary input into logic circuit.