Shin-Ichiro Ideta
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Shin-Ichiro Ideta has a total of 30 co-authors. Here are the top co-authors by number of shared publications:
- Akira Iyo
National Institute of Advanced Industrial Science and Technology (AIST)
1 shared publication - Atsushi Fujimori
University of Tokyo 1 Department of Physics Bunkyo-ku, Tokyo 113-0033, Japan
1 shared publication - Atsushi Fujimori
National Synchrotron Radiation Research Center, Hsinchu, Taiwan
1 shared publication - Chul-Ho Lee
National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568, Japan
1 shared publication - D. -H. Lu
Stanford Synchrotron Radiation Lightsource SLAC National Accelerator Laboratory 94025 Menlo Park CA USA
1 shared publication Donghui Lu
Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo, Japan
1 shared publication
Latest Publications
- Open Access
- 1 April 2014
- Published by Frontiers Media SA in Frontiers in Physics
- Vol. 2
Orbital character and electron correlation effects on two- and three-dimensional Fermi surfaces in KFe2As2 revealed by angle-resolved photoemission spectroscopy
We have investigated orbital character and electron correlation effects on Fermi surfaces in the hole-overdoped iron pnictide superconductor KFe2As2, which shows a low Tc of ~4 K, by angle-resolved photoemission spectroscopy. From the polarization-dependence of the ARPES spectra, we have determined the orbital character of each Fermi surface. Electron mass renormalization of each band is quantitatively consistent with de Haas-van Alphen results. The outer β and middle ζ Fermi surfaces show large renormalization factor of m*/mb ~6–7, while the inner α Fermi surface has a smaller factor m*/mb ~2. Middle hole Fermi surface ζ has strong three-dimensionality compared to other Fermi surfaces, indicating the d3z2–r2 orbital character, which may be related to the “octet-line nodes” recently observed by laser ARPES. The observed orbital-dependent mass renormalization would give constraints on the pairing mechanism with line nodes of this system.
- 1 April 2014
- Published by Frontiers Media SA in Frontiers in Physics
- Vol. 2
Open AccessOrbital character and electron correlation effects on two- and three-dimensional Fermi surfaces in KFe2As2 revealed by angle-resolved photoemission spectroscopy
We have investigated orbital character and electron correlation effects on Fermi surfaces in the hole-overdoped iron pnictide superconductor KFe2As2, which shows a low Tc of ~4 K, by angle-resolved photoemission spectroscopy. From the polarization-dependence of the ARPES spectra, we have determined the orbital character of each Fermi surface. Electron mass renormalization of each band is quantitatively consistent with de Haas-van Alphen results. The outer β and middle ζ Fermi surfaces show large renormalization factor of m*/mb ~6–7, while the inner α Fermi surface has a smaller factor m*/mb ~2. Middle hole Fermi surface ζ has strong three-dimensionality compared to other Fermi surfaces, indicating the d3z2–r2 orbital character, which may be related to the “octet-line nodes” recently observed by laser ARPES. The observed orbital-dependent mass renormalization would give constraints on the pairing mechanism with line nodes of this system.
- 3 September 2013
- Published by American Physical Society (APS) in Physical Review B
- Vol. 88 (10) , 100501
Absence of superconductivity in the hole-doped Fe pnictide Ba(FeMn)As: Photoemission and x-ray absorption spectroscopy studiesWe have studied the electronic structure of Ba(FeMn)As (), which fails to become a superconductor in spite of the formal hole doping like BaKFeAs, with photoemission spectroscopy and x-ray absorption spectroscopy (XAS). With decreasing temperature, a transition from the paramagnetic phase to the antiferromagnetic phase was clearly observed by angle-resolved photoemission spectroscopy. XAS results indicated that the substituted Mn atoms form a strongly hybridized ground state. Resonance-photoemission spectra at the Mn edge revealed that the Mn partial density of states is distributed over a wide energy range of 2–13 eV below the Fermi level (), with little contribution around . This indicates that the dopant Mn 3 states are localized in spite of the strong Mn –As hybridization and split into the occupied and unoccupied parts due to the on-site Coulomb and exchange interaction. The absence of superconductivity in Ba(FeMn)As can thus be ascribed both to the absence of carrier doping in the FeAs plane and to the stabilization of the competing G-type antiferromagnetic order by the Mn impurities.- 3 September 2013
- Published by American Physical Society (APS) in Physical Review B
- Vol. 88 (10) , 100501
Absence of superconductivity in the hole-doped Fe pnictide Ba(FeMn)As: Photoemission and x-ray absorption spectroscopy studiesWe have studied the electronic structure of Ba(FeMn)As (), which fails to become a superconductor in spite of the formal hole doping like BaKFeAs, with photoemission spectroscopy and x-ray absorption spectroscopy (XAS). With decreasing temperature, a transition from the paramagnetic phase to the antiferromagnetic phase was clearly observed by angle-resolved photoemission spectroscopy. XAS results indicated that the substituted Mn atoms form a strongly hybridized ground state. Resonance-photoemission spectra at the Mn edge revealed that the Mn partial density of states is distributed over a wide energy range of 2–13 eV below the Fermi level (), with little contribution around . This indicates that the dopant Mn 3 states are localized in spite of the strong Mn –As hybridization and split into the occupied and unoccupied parts due to the on-site Coulomb and exchange interaction. The absence of superconductivity in Ba(FeMn)As can thus be ascribed both to the absence of carrier doping in the FeAs plane and to the stabilization of the competing G-type antiferromagnetic order by the Mn impurities.