Optical pseudogap from iron states in filled skutterudites AFe4Sb12 (A=Yb, Ca, Ba).
Optical investigations are presented of the filled skutterudites AFe4Sb12 with divalent cations A=Yb, Ca, Ba. For each of these compounds a very similar pseudogap structure in the optical conductivity develops in the far-infrared spectral region at temperatures below 90 K. Highly accurate local-density approximation electronic band structure calculations can consistently explain the origin of the pseudogap structure generated largely by transition metal 3d states. In particular, a 4f-conduction electron hybridization or strong correlations can be ruled out as origin for the pseudogap.
Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Strasse 40, 01187 Dresden, Germany.
J
J
Sichelschmidt
V
V
Voevodin
H J
HJ
Im
S
S
Kimura
H
H
Rosner
A
A
Leithe-Jasper
W
W
Schnelle
U
U
Burkhardt
J A
JA
Mydosh
Yu
Y
Grin
F
F
Steglich