Metal-insulator transition in manganites: Changes in optical conductivity up to 22 eV
Artikel i vetenskaplig tidskrift, 2008
The electronic response of doped manganites at the transition from the paramagnetic insulating to the ferromagnetic metallic state in La(1-x)Ca(x)MnO(3) for x=0.3 and 0.2 was investigated by dc conductivity, ellipsometry, and vacuum ultraviolet reflectance for energies between 0 and 22 eV. A stabilized Kramers-Kronig transformation yields the optical conductivity and reveals changes in the optical spectral weight up to 22 eV at the metal-to-insulator transition. In the observed energy range, the spectral weight is conserved within 0.3%. The redistribution of spectral weight in this surprisingly broad energy range has important ramifications for the effective low-energy physics. We discuss the importance of the charge-transfer, Coulomb on-site, Jahn-Teller, and long-range Coulomb screening effects to the electronic structure.
excitations
electronic-structure
orbital waves
la1-xsrxmno3
la0.7ca0.3mno3 films
charge
narrow energy bands
phase-separation
lamno3
photoemission spectra
Författare
A. Rusydi
Ralf Rauer
Chalmers, Teknisk fysik, Kondenserade materiens fysik
G. Neuber
M. Bastjan
I. Mahns
S. Muller
P. Saichu
B. Schulz
S. G. Singer
A. I. Lichtenstein
D. Qi
X. Gao
X. Yu
A. T. S. Wee
G. Stryganyuk
K. Dorr
G. A. Sawatzky
S. L. Cooper
M. Rubhausen
Physical Review B - Condensed Matter and Materials Physics
24699950 (ISSN) 24699969 (eISSN)
Vol. 78 12 125110 (art. no.)-Ämneskategorier
Den kondenserade materiens fysik
DOI
10.1103/PhysRevB.78.125110