421 citations · 1.3k across the 23 of their papers we have counts for
23 papers
Rapid and Scalable Synthesis of Alkali Metal-Intercalated C Superconductors
Akira Iyo, Hiroshi Fujihisa, Yoshito Gotoh +4
Alkali metal-intercalated C, ( = K, Rb, Cs, and their combinations), holds significant potential for practical applications due to its high superconducting…
Accelerated Lanthanide Intercalation into Graphite Catalyzed by Na
Akira Iyo, Hiroshi Fujihisa, Yoshito Gotoh +4
Lanthanides () are notoriously difficult to intercalate into graphite. We investigated the possibility of using Na to catalyze the formation of -intercalated graphite and s…
Na-catalyzed rapid synthesis and characterization of intercalated graphite CaC6
Akira Iyo, Hiroshi Fujihisa, Yoshito Gotoh +4
In this study, we conducted experiments on CaC6 for elucidating the Na-catalyzed formation mechanism and achieving rapid mass synthesis of graphite intercalation compounds (GICs).…
Uniaxial negative thermal expansion in an orthorhombic superconductor CoZr3
Hiroto Arima, Tatsuki Inui, Aichi Yamashita +5
We investigated the temperature evolution of crystal structure of orthorhombic CoZr3, which is a superconductor with a transition temperature of 4.3 K, by synchrotron and laborator…
Hidden Structural and Superconducting Phase Induced in Antiperovskite Arsenide SrPdAs
Akira Iyo, Hiroshi Fujihisa, Yoshito Gotoh +5
Enriching the material variation often contributes to the progress of materials science. We have discovered for the first time antiperovskite arsenide SrPdAs and revealed a h…
High-pressure synthesis and superconductivity of the novel Laves phase BaIr2
Terunari Koshinuma, Hiroki Ninomiya, Izumi Hase +8
Superconductors comprising 5d transition metals of Ir and Pt have been widely explored because they have the potential of unique superconductivity caused by the strong spin-orbit i…
Posttreatment Effects on the Crystal Structure and Superconductivity of Ca-Free Double-Layered Cuprate SrSrCuOF
Hiroki Ninomiya, Kenji Kawashima, Hiroshi Fujihisa +6
We report the effects of low-temperature postannealing on the structural and superconducting properties of the recently discovered Ca-free double-layered cuprate, SrSrCuO$_…
Antiperovskite superconductor LaPdP with noncentrosymmetric cubic structure
Akira Iyo, Izumi Hase, Hiroshi Fujihisa +8
Antiperovskites are a promising candidate structure for the exploration of new materials. We discovered an antiperovskite phosphide, LaPdP, following our recent synthesis of…
Superconductivity of centrosymmetric and non-centrosymmetric phases in antiperovskite (Ca,Sr)PdP
Akira Iyo, Izumi Hase, Hiroshi Fujihisa +9
In the recently discovered antiperovskite phosphide (Ca,Sr)PdP, centrosymmetric (CS) and non-centrosymmetric (NCS) superconducting phases appear depending on the Sr concentrati…
Experimental and Computational Determination of Optimal Boron Content in Layered Superconductor ScCBC
Hiroki Ninomiya, Terunari Koshinuma, Taichiro Nishio +9
It is generally difficult to quantify the amounts of light elements in materials because of their low X-ray-scattering power, as this means that they cannot be easily estimated via…
Structural phase transitions and superconductivity induced in antiperovskite phosphide CaPdP
Akira Iyo, Hiroshi Fujihisa, Yoshito Gotoh +7
In this study, we succeeded in synthesizing new antiperovskite phosphides PdP ( = Ca, Sr, Ba) and discovered the appearance of a superconducting phase (0.17 $\…
Beryllium Polyhydride Be4H8(H2)2 Synthesized at HP/HT
Takahiro Matsuoka, Hiroshi Fujihisa, Takahiro Ishikawa +6
We report the XRD and Raman scattering measurements in combination with DFT calculations that reveal the formation of beryllium polyhydride Be4H8(H2)2 by laser heating Be/H2 mixtur…
Superconductivity in a Scandium Borocarbide with a Layered Crystal Structure
Hiroki Ninomiya, Kunihiko Oka, Izumi Hase +8
The discovery of nearly room-temperature superconductivity in superhydrides has motivated further materials research for conventional superconductors. To realize the moderately hig…
Superconductivity induced by Mg deficiency in non-centrosymmetric phosphide MgRhP
Akira Iyo, Izumi Hase, Hiroshi Fujihisa +7
The search for non-centrosymmetric superconductors that may exhibit unusual physical properties and unconventional superconductivity has yielded the synthesis of a non-centrosymmet…
Superconductivity in Uncollapsed Tetragonal LaFe2As2
Akira Iyo, Shigeyuki Ishida, Hiroshi Fujihisa +5
We report synthesis, crystal structure and superconductivity in ThCr2Si2-type LaFe2As2 (La122). La122 was synthesized at 960°C for 1.5 h under a pressure of 3.4 GPa. An as-synthesi…
Collapse of CuO Double Chains and Suppression of Superconductivity in High-Pressure Phase of YBaCuO
Atsuko Nakayama, Yusuke Onda, Shuhei Yamada +8
The crystal structure and electrical resistivity of YBaCuO (Y124) were studied under high pressure up to 18 GPa using diamond-anvil cells, respectively, in order to cla…
Discovery of New Layered Iron Arsenide Superconductor (Ca,Pr)FeAs2
Hiroyuki Yakita, Hiraku Ogino, Tomoyuki Okada +9
A new iron-based superconductor (Ca,Pr)FeAs2 was discovered. Plate-like crystals of the new phase were obtained and crystal structure was investigated by single-crystal X-ray diffr…
Pressure-induced Enhancement of Superconductivity in BiS-layered LaOFBiS
Takahiro Tomita, Masaya Ebata, Hideto Soeda +9
The newly discovered BiS-based LaOFBiS (=0.5) becomes superconductive at =2.5 K. Electrical resistivity and magnetization measurements are performed u…
BiS2 - based superconductivity in F-substituted NdOBiS2
Satoshi Demura, Yoshikazu Mizuguchi, Keita Deguchi +12
We have successfully synthesized a new BiS2-based superconductor NdOBiS2 with F-doping. This compound is composed of superconducting BiS2 layers and blocking NdO layers, which indi…
Novel BiS2-based layered superconductor Bi4O4S3
Yoshikazu Mizuguchi, Hiroshi Fujihisa, Yoshito Gotoh +7
Exotic superconductivity has often been discovered in materials with a layered (two-dimensional) crystal structure. The low dimensionality can affect the electronic structure and c…
Superconductivity in novel BiS2-based layered superconductor LaO1-xFxBiS2
Yoshikazu Mizuguchi, Satoshi Demura, Keita Deguchi +5
Layered superconductors have provided some interesting fields in condensed matter physics owing to the low dimensionality of their electronic states. For example, the high-Tc (high…
Na-Au intermetallic compounds formed under high pressure at room temperature
K. Takemura, H. Fujihisa
High-pressure powder x-ray diffraction experiments have revealed that sodium and gold react at room temperature and form new Na-Au intermetallic compounds under high pressure. We h…
The "devil's staircase" type phase transition in NaV2O5 under high pressure
K. Ohwada, Y. Fujii, N. Takesue +12
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-…