A5051679404- High-pressure geophysics and materials
- Geological and Geochemical Analysis
- Rare-earth and actinide compounds
- Iron-based superconductors research
- Magnetic and transport properties of perovskites and related materials
- Advanced Condensed Matter Physics
- earthquake and tectonic studies
- Electronic and Structural Properties of Oxides
- X-ray Diffraction in Crystallography
- Quantum, superfluid, helium dynamics
- Superconductivity in MgB2 and Alloys
- Organic and Molecular Conductors Research
- Physics of Superconductivity and Magnetism
- Advanced Chemical Physics Studies
- Thermal Expansion and Ionic Conductivity
- Chemical Thermodynamics and Molecular Structure
- Crystallography and molecular interactions
- Crystal Structures and Properties
- 2D Materials and Applications
- Inorganic Chemistry and Materials
- Thermodynamic and Structural Properties of Metals and Alloys
- Nuclear Physics and Applications
- Hydrogen Storage and Materials
- High Entropy Alloys Studies
- MXene and MAX Phase Materials
Japan Synchrotron Radiation Research Institute
2017-2025
SPring-8
2017-2025
Life Science Institute
2017-2021
Tokyo Institute of Technology
1984-2021
University of Hyogo
2020-2021
National Institute for Materials Science
2020
Shizuoka University
1997
Very recently, a new superconductor with Tc = 80 K has been reported in nickelate (La3Ni2O7) at around 15–40 GPa conditions (Nature, 621, 493, 2023), which is the second type of unconventional superconductor, besides cuprates, above liquid nitrogen temperature. However, phase diagram plotted this report was mostly based on transport measurement under low-temperature and high-pressure conditions, assumed corresponding X-ray diffraction (XRD) results were carried out room This encouraged us to...
An overview of the recently renovated high-pressure X-ray diffraction (XRD) BL10XU beamline for diamond anvil cell at SPring-8 is presented. The renovation includes replacement source and monochromator, enhanced focusing systems high-energy XRD, recent progress in sample environment control techniques that are available studies. Other simultaneous measurement combination with such as Raman scattering spectroscopy Mössbauer spectroscopy, have been developed to obtain complementary information...
The density of liquid iron has been determined up to 116 GPa and 4350 K via static compression experiments following an innovative analysis diffuse scattering from liquid. longitudinal sound velocity was also obtained 45 2700 based on inelastic x-ray measurements. Combining these results with previous shock-wave data, we determine a thermal equation state for iron. It indicates that Earth's outer core exhibits 7.5%–7.6% deficit, 3.7%–4.4% excess, almost identical adiabatic bulk modulus,...
Superconductivity has been observed in many insulating transition metal dichalcogenides (TMDCs) under pressure. However, the origin of superconductivity remains elusive due to lack studies on their structures at low temperatures. Here, we report observation a high-T_{c} superconducting state (SC-I phase) coexisting with other states compressed 1T-HfS_{2} crystal up approximately 160 GPa. In situ synchrotron x-ray diffraction results exclude presence decomposed sulfur and confirm two...
Superconductive H3S synthesized from H2S is very poorly crystallized, and has excess sulfur as impurity (3H2S -> 2H3S + S). The phase transition process undergoes in condition, which might cause hydrogen deficiency. influence of deficiency not clear. Therefore investigation on the superconductivity with no demanded. Two groups performed synthesis elemental (direct synthesis) their results have shown that caused when direct under excessive condition. However, measurements been carried out...
Spin state transitions and intermetallic charge transfers can essentially change material structural physical properties while excluding external chemical doping. However, these two effects have rarely been found to occur sequentially in a specific material. In this article, we show the realization of phenomena perovskite oxide PbCoO3 with simple ABO3 composition under high pressure. possesses peculiar A- B-site ordered distribution Pb2+Pb4+3Co2+2Co3+2O12 insulating behavior at ambient...
The structural stability of transition metal vanadium (V) under high pressure is investigated by using an x-ray diffraction technique combined with a laser annealing method. Although the body-centered cubic (bcc) phase V showed rhombohedral distortion above 30–69 GPa, as reported in previous studies, increasing at 298 K, was eliminated 58, 118, 119, and 189 GPa up to 2200 K; bcc observed room temperature after annealing. These results suggested that stable temperature, angle α >...
$\rm{RuO_2}$ stands as a quintessential rutile-type compound under ambient conditions, with its structural exploration pressure bearing significant implications for both phase transition investigations and Earth science. Nonetheless, the precise sequence remains debate. In this study, we disclose emergence of $Pbca$ alongside enduring metallic character megabar pressure. Employing state-of-the-art synchrotron X-ray diffraction, our observations delineate trajectory progressing through...
The order or disorder of electrons is fundamental to materials properties and also provides simple analogues the different states matter. A charge ordered (CO) insulating state, analogous a crystalline solid, observed in many mixed valence materials. On heating, this melts liquid (metallic) phase, often with interesting associated physics functions such as Verwey transition Fe3O4, colossal magnetoresistances manganites (e.g., La0.5Ca0.5MnO3), superconductivity K-doped BaBiO3. Here we report...
The densities of liquid materials at high pressures and temperatures are important information to understand the elastic behavior liquids extreme conditions, which is closely related formation evolution processes Earth planetary interiors. x-ray absorption method an effective measure density non-crystalline pressures. However, temperature condition using a diamond anvil cell (DAC) has been limited 720 K date. To significantly expand measurable this method, in study, we developed measurement...
The formation of titanium dioxides, such as rutile and anatase, is known to proceed through the a lepidocrocite-type layered structure under hydrothermal conditions, but nucleation this intermediate still not understood well. Here, titanates conditions observed by tracking structural changes in situ time-resolved pair distribution function analyses. We found that titanate clusters or corrugated prestructures having <1 nm domains with connectivity were formed even before thermal treatment...
We report on the crystal structure and electronic properties of heavy fermion superconductor UTe2 at high pressure up to 11 GPa, as investigated by X-ray diffraction electrical resistivity experiments. The measurements under using a synchrotron light source reveal anisotropic linear compressibility unit cell 3.5 while pressure-induced structural phase transition is observed above 3.5-4GPa room temperature, where body-centered orthorhombic with space group Immm changes into tetragonal I4/mmm....
Two-dimensional (2D) metal–organic frameworks (MOFs) are a class of materials exhibiting various functionalities based on anisotropic layered structures constructed through strong in-plane connectivity and weak van der Waals interlayer interaction. However, their mechanical properties modulation 2D-MOF crystals have been rarely investigated. Herein, we report the compression elastic two 2D-MOFs, [Mn(salen)]2[Pt(CN)4]·H2O (1) [Mn(salen)]2[PtI2(CN)4]·H2O (2), composed undulating layers. These...
Abstract The sound velocity of liquid Fe 47 Ni 28 S 25 and 63 12 was measured up to 52 GPa/2480 K in externally resistance‐heated laser‐heated diamond‐anvil cells using high‐resolution inelastic X‐ray scattering. From these experimental data, we obtained the elastic parameters , S0 = 96.1 ± 2.7 GPa ′ 4.00 0.13, where are adiabatic bulk modulus its pressure derivative at 1 bar, when density is fixed ρ 0 5.62 0.09 g/cm 3 for bar 2000 K. With parameters, were calculated be 8.41 0.17 km/s 8.93...
We determined the electrical resistivity of liquid Fe to 135 GPa and 6680 K using a four-probe method in diamond-anvil cell combined with two novel techniques: (i) enclosing molten sapphire capsule, (ii) millisecond time-resolved simultaneous measurements resistance, x-ray diffraction, temperature instantaneously melted Fe. Our results show minimal dependence its anomalous decrease around 50 GPa, likely associated gradual magnetic transition, both agreement previous ab initio...
Superconductivity is one of most intriguing quantum phenomena, and the quest for elemental superconductors with high critical temperature ( T c ) great scientific significance due to their relatively simple material composition underlying mechanism. Here we report experimental discovery densely compressed scandium (Sc) becoming first superconductor breaking into 30 K range, which comparable values classic La–Ba–Cu–O or LaFeAsO superconductors. Our results show that <?CDATA...
Very recently, a new superconductor with Tc = 80 K was reported in nickelate (La3Ni2O7) at around 15 - 40 GPa conditions (Nature, 621, 493, 2023) [1], which is the second type of unconventional superconductor, beside cuprates, above liquid nitrogen temperature. However, phase diagram plotted this report mostly based on transport measurement low temperature and high pressure conditions, assumed corresponding X-ray diffraction (XRD) results carried out room This encouraged us to carry situ...
The effect of pressure on the crystal structure ${\mathrm{Ni}}_{2}\mathrm{MnGa}$ was investigated up to 41 GPa using in situ angle-dispersive x-ray diffraction with synchrotron radiation, an imaging plate detector, and a diamond anvil cell. A pressure-induced transition from cubic $L{2}_{1}$ (space group $\mathit{Fm}\overline{3} m$) 10-layer modulated monoclinic ($C2/m$) distortion $\ensuremath{\beta}\ensuremath{\sim}{92}^{\ensuremath{\circ}}$ occurred at 19.1 or lower. volume change...
We performed variable-temperature synchrotron powder X-ray diffraction measurements and impedance spectroscopy under pressure for silver iodide (AgI) nanoparticles with a diameter of 11 nm. The superionic conducting α-phase AgI was successfully stabilized down to at least 20 °C by applying 0.18 GPa, whereas the transition temperature 147 in bulk ambient pressure. To our knowledge, this is first example existing stably room temperature.