A5074115978- Rare-earth and actinide compounds
- Magnetic and transport properties of perovskites and related materials
- Magnetic Properties of Alloys
- Iron-based superconductors research
- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- Inorganic Chemistry and Materials
- Molecular spectroscopy and chirality
- Multiferroics and related materials
- Analytical Chemistry and Chromatography
- High-pressure geophysics and materials
- Marine Toxins and Detection Methods
- Magnetic properties of thin films
- Magnetic Properties and Applications
- Thermodynamic and Structural Properties of Metals and Alloys
- Synthetic Organic Chemistry Methods
- Solid-state spectroscopy and crystallography
- Advanced Chemical Physics Studies
- Boron and Carbon Nanomaterials Research
- Crystallization and Solubility Studies
- Nicotinic Acetylcholine Receptors Study
- Electronic and Structural Properties of Oxides
- Semiconductor materials and devices
- Integrated Circuits and Semiconductor Failure Analysis
- Semiconductor materials and interfaces
Saitama University
2012-2023
Saga University
2011
Iwate University
2011
Kindai University
2009
Tohoku University
1996-2005
Urawa University
1999-2004
Nagoya University
1994-1996
Nihon University
1991
Kyoto University
1972
We show that single-crystalline ${\mathrm{Sr}}_{3}{\mathrm{Ru}}_{2}{\mathrm{O}}_{7}$ grown by a floating-zone technique is an isotropic paramagnet and quasi-two-dimensional metal, as spin-triplet superconducting ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ is. The ground state Fermi liquid with very low residual resistivity $(\ensuremath{\approx}3 \ensuremath{\mu}\ensuremath{\Omega}\mathrm{cm}$ for in-plane currents) nearly ferromagnetic metal the largest Wilson ratio ${R}_{\mathrm{W}}>~10$ among...
Magnetic properties were investigated on a single-crystalline DyB 2 C compound with the tetragonal structure. Spontaneous magnetizations appear along a- and [1 1 0]-directions below T =15.3 K. A very small shoulder is observed only c -axis at Q =24.7 K, although large λ-type anomalous specific heats are . There exists magnetic anisotropy in basal plane which magnetization processes Neutron powder diffraction experiments reveal that reflections In magnetically ordered phase, Dy moments...
Single crystals of a highly conductive oxide SrMoO3 have been grown by floating-zone method under argon atmosphere with ultralow oxygen partial pressure p(O2)∼10−25atm. The obtained single reveal quite low resistivity at 300 K ρ(300K)=5.1μΩcm, which is the lowest to date in values ρ(300K) all oxides. Resistivity and specific heat data suggest that electrons behave as Fermi liquid (correlated electron), its due extremely small electron-phonon interaction SrMoO3.
We have measured the electrical resistivity of a single crystal YbCo 2 Zn 20 at pressures up to 2.37 GPa and temperatures from 50 mK 300 K. Above critical pressure P c (∼1 GPa), we found anomaly T M (∼0.15 K 1 GPa) that increases with pressure. At ambient pressure, system shows nonmagnetic ground state described by Fermi-liquid model. The coefficient A strongly upon approaching . However, in vicinity , temperature dependence deviates description. These observations suggest application...
Magnetic susceptibility, magnetization process, specific heat, ultrasonic velocity, and inelastic neutron scattering experiments were performed on powdered single-crystalline ${\mathrm{TmAu}}_{2}$ samples. with a simple body-centered tetragonal ${\mathrm{MoSi}}_{2}$-type structure undergoes transition to an antiferromagnetic state at ${T}_{N}$ of 3.2 K. An anomaly 7.0 K is observed in the temperature dependence heat magnetic susceptibility. A very large softening beyond 50% from 300 down...
The Ni–Cr–Al Russian alloy was prepared. Its magnetic and mechanical properties were better than those of MP35N alloy. We fabricated the a piston–cylinder-type hybrid high-pressure cell using It has been found that maximum working pressure can be repeatedly raised to 3.5 GPa at T = 2 K without any difficulties.
We have succeeded in growing single crystals of ${\mathrm{Ca}}_{3}{\mathrm{Ru}}_{2}{\mathrm{O}}_{7}$ using a floating-zone method. The temperature dependence the electrical resistivity establishes that develops quasi-two-dimensional metallic ground state below $30\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, from which observed quantum oscillation derives. specific heat reveals electronic specific-heat coefficient $\ensuremath{\gamma}$ to be as small...
Abstract Enantiopure phthalides 2 and 5 – 8 were synthesized via enantioresolution of the corresponding alcohols with a chiral auxiliary camphorsultam dichlorophthalic acid, (1 S ,2 R ,4 )‐(−)‐CSDP acid 3, followed by solvolysis KOH in MeOH catalytic oxidation glycols iridium complex 28. The absolute configurations determined applying 1 H‐NMR anisotropy method MαNP ( 4 ), 2‐methoxy‐2‐(1‐naphthyl)propionic to synthetic precursory alcohols. In case 3‐phenylphthalide )‐(−)‐ 7 , configuration...
We report a uniaxial pressure-dependence of magnetism in layered perovskite strontium ruthenate Sr3Ru2O7. By applying relatively small pressure, greater than 0.1 GPa normal to the RuO2 layer, ferromagnetic ordering manifests below 80 K from enhanced-paramagnet. Magnetization at 1 kOe and 2 becomes 100 times larger that under ambient condition. Uniaxial pressure dependence Curie temperature T_C suggests first order magnetic transition. Origin this uniaxial-pressure induced ferromagnetism is...
We have characterized the ground state of Sr3Ir2O7 by performing measurements electrical resistivity, magnetic susceptibility, magnetization, specific heat and electron diffraction (ED). Polycrystalline samples been synthesized using a high-pressure technique. exhibits weak ferromagnetism with small ferromagnetic component (2 × 10−3 μB/Ir) below TC∼280 K. The temperature dependence resistivity ρ shows semiconducting-like behaviour; dρ/dT<0 an anomaly near TC. From result for heat, λ-type...
In the intermetallic SmNiC${}_{2}$, ferromagnetic metallic state competes with charge-density-wave state. We can switch by applying a magnetic field that is conjugated to magnetization of order parameter in state, and show giant negative magnetoresistance. Under applied field, resistivity becomes one magnitude smaller than zero-field resistivity.
We have demonstrated that ferroelectric polarization in a spin-driven multiferroic CuFe${}_{1\ensuremath{-}x}$Ga${}_{x}$O${}_{2}$ with $x=0.035$ can be controlled by the application of uniaxial pressure. Our neutron-diffraction and $\mathit{in}$ situ ferroelectric-polarization measurements revealed pressure dependence is explained repopulation three types magnetic domains originating from trigonal symmetry crystal. conclude anisotropic lattice distortion fixed relationship between directions...
The HIJKLM ring segment (27) of the right half portion ciguatoxin CTX3C (1) has been synthesized using a ring-closing reaction mediated by low-valent titanium reagent.
We present the highly frustrated phenomena observed in YbAl 3 C with a spin gap. The inelastic neutron spectra of low-lying magnetic excitations at low temperatures are quite similar to those SrCu 2 (BO ) and (CuCl)LaNb O 7 that exhibit dimer ground state two-dimensional quantum system. structure first excited triplet is directly clarified by scattering experiments higher energy resolution. Furthermore, it becomes clear characteristic remain within high-temperature region. result specific...
We have investigated effects of applied uniaxial pressure ( p ) on magnetic phase transitions in a triangular lattice antiferromagnet CuFeO 2 (CFO) and slightly Ga-substituted compound CuFe 1- x Ga O (CFGO) with =0.018. performed neutron diffraction, spherical polarimetry, susceptibility pyroelectric measurements under up to 100 MPa the [1\bar10] surfaces single crystal samples. As result, we revealed that both CFO CFGO =0.018), application significantly increases transition temperature from...
The $4f$-electron system YbAl${}_{3}$C${}_{3}$ with a nonmagnetic spin-dimer ground state has been studied by neutron diffraction in an applied magnetic field. A long-range order involving both ferromagnetic and antiferromagnetic components revealed above the critical field ${H}_{C}\ensuremath{\sim}6$ T at temperature $T=0.05$ K. structure indicates that geometrical frustration of prototype hexagonal lattice is not fully relieved low-temperature orthorhombic phase. suppression ordering...
We report the electronic structure of a prototypical valence fluctuation system, YbAl${}_{2}$, using angle-resolved photoemission spectroscopy. The observed band dispersions and Fermi surfaces are well described in terms calculations based on local density approximation. Strong hybridization between conduction 4$f$ bands is identified basis periodic Anderson model. evaluated small mass enhancement factor high Kondo temperature qualitatively agree with those obtained from thermodynamic...
We have investigated two-dimensional spin systems SrCu2(BO3)2 and Nd2BaZnO5, both of which a unique topology that is equivalent to the Shastry-Sutherland lattice. The magnetization curve reveals that, unlike 1/8 1/4 plateaux, 1/3 plateau very stable, surviving at least up 69 T. pressure dependence susceptibility 10 kbar indicates causes system approach critical point some other states. On hand, Nd2BaZnO5 with rather classical spins exhibits an antiferromagnetic long range ordering 2.4 K....
meta-Substituted diphenylmethanols were enantioresolved by the method of chiral phthalic acid yielding enantiopure alcohols. Their absolute configurations unambiguously determined X-ray crystallography phthalate esters and/or (1)H NMR anisotropy using 2-methoxy-2-(1-naphthyl)propionic acid.
The spinel GeCo 2 O 4 has the pyrochlore lattice of Co 2+ ions, in which kagomé and triangular planes stack alternately along [111] direction. It shows antiferromagnetic ordering below T N ∼21 K with a characteristic wave vector Q M =(1/2,1/2,1/2). spin arrangement is ferromagnetic between as well planes. exhibits magnetic phase transition at H ∼4 T. Powder neutron diffraction measurements were performed on ambient field. Our results are consistent structure model behave independently field,...