Shin-ichi Fujimori

4f-derived Fermi surfaces of CeRu2(Si1-xGex)2 near the quantum critical point: resonant soft-X-ray ARPES study.

Angle-resolved photoelectron spectroscopy in the Ce 3d-->4f excitation region was measured for the paramagnetic state of CeRu2Si2, CeRu2(Si0.82Ge0.18)2, and LaRu2Si2 to investigate the changes of the 4f electron Fermi surfaces around the quantum critical point. While the difference of the Fermi surfaces between CeRu2Si2 and LaRu2Si2 was experimentally confirmed, a strong 4f-electron character was observed in the band structures and the Fermi surfaces of CeRu2Si2 and CeRu2(Si0.82Ge0.18)2, consequently indicating a delocalized nature of the 4f electrons in both compounds. The absence of Fermi surface reconstruction across the critical composition suggests that SDW quantum criticality is more appropriate than local quantum criticality in CeRu2(Si1-xGex)2.

Itinerant U 5 f band states in the layered compound UFeGa 5 observed by soft x-ray angle-resolved photoemission spectroscopy

We have performed angle-resolved photoemission spectroscopy (ARPES) experiments on paramagnetic UFeGa5 using soft X-ray synchrotron radiation (hn=500eV) and derived the bulk- and U 5f-sensitive electronic structure of UFeGa5. Although the agreement between the experimental band structure and the LDA calculation treating U 5f electrons as being itinerant is qualitative, the morphology of the Fermi surface is well explained by the calculation, suggesting that the U 5f states can be essentially understood within the itinerant-electron model.

Electronic Structure of Heavy Fermion Uranium Compounds Studied by Core-Level Photoelectron Spectroscopy

High-energy-resolution core-level and valence-band photoelectron spectroscopic studies were performed for the heavy fermion uranium compounds UGe 2 , UCoGe, URhGe, URu 2 Si 2 , UNi 2 Al 3 , UPd 2 Al 3 , and UPt 3 as well as typical localized and itinerant uranium compounds to understand the relationship between the uranium valence state and their core-level spectral line shapes. In addition to the main line and high-binding energy satellite structure recognized in the core-level spectra of uranium compounds, a shoulder structure on the lower binding energy side of the main lines of localized and nearly localized uranium compounds was also found. The spectral line shapes show a systematic variation depending on the U 5 f electronic structure. The core-level spectra of UGe 2 , UCoGe, URhGe, URu 2 Si 2 , and UNi 2 Al 3 are rather similar to those of itinerant compounds, suggesting that U 5 f electrons in these compounds are well hybridized with ligand states. On the other hand, the core-level spectra of UPd ...

Direct observation of a quasiparticle band in CeIrIn5 : An angle-resolved photoemission spectroscopy study

We have performed a high-resolution angle resolved Ce 4

Itinerant magnetism in URhGe revealed by angle-resolved photoelectron spectroscopy

d-4f

Itinerant nature of U 5 f states in uranium mononitride revealed by angle-resolved photoelectron spectroscopy

resonant photoemission experiment on the heavy fermion superconductor CeIrIn

Splitting in the Fermi surface of ZrTe3 : A surface charge density wave system

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X-Ray Photoelectron Spectroscopy Study of U(Rh 1-xPdx) 3 Alloys

. We have observed a quasi-particle band which has an energy dispersion of

Electronic structures of ferromagnetic superconductorsUGe2and UCoGe studied by angle-resolved photoelectron spectroscopy

\sim 30

Band structures of 4f and 5f materials studied by angle-resolved photoelectron spectroscopy

meV in the Ce 4