Anomalous duality of 4f electrons in filled skutterudite CeOs4Sb12.
We study the electronic structure of the filled skutterudite CeOs4Sb12 using photoemission spectroscopy (PES). Soft x-ray excited Ce 3d-4f resonant PES confirms the existence of Ce 4f states at the Fermi level (EF). Temperature dependent high-resolution laser-PES spectra reveal a pseudogap formation around EF, which can be explained in terms of the hybridization gap. Simultaneously, a sharp feature is formed just above EF with decreasing temperature. The heavy-fermion-like specific heat is attributed to the occupation of this feature. The results identify the origin of the anomalous coexistence of heavy-fermion and pseudogap behavior in terms of a symmetry dependent hybridization.
Matsunami
M
M
RIKEN SPring-8 Center, Sayo-gun, Hyogo 679-5148, Japan. matunami@spring8.or.jp
Eguchi
R
R
Kiss
T
T
Horiba
K
K
Chainani
A
A
Taguchi
M
M
Yamamoto
K
K
Togashi
T
T
Watanabe
S
S
Wang
X-Y
XY
Chen
C-T
CT
Senba
Y
Y
Ohashi
H
H
Sugawara
H
H
Sato
H
H
Harima
H
H
Shin
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