Spectral functions in doped transition metal oxides
Solid State and Structural Chemistry Unit, Indian Institute of
Bangalore 560012, India
2 Serin Physics Laboratory, Rutgers University, Piscataway, NJ 08855, USA
Accepted: 16 September 1996
We present experimental photoemission and inverse photoemission spectra of representing electron-doped systems. Photoemission spectra in the presence of electron doping exhibit prominent features arising from electron correlation effects, while the inverse photoemission spectra are dominated by spectral features explainable within single-particle approaches. We show that such a spectral evolution in chemically doped correlated systems is not compatible with expectations based on Hubbard or any other similar model. We present a new theoretical approach taking into account the inhomogeneity of the real system which gives qualitatively different results compared to standard homogeneous models and is in quantitative agreement with experiments.
PACS: 79.60.Bm – Clean metal, semiconductor, and insulator surfaces / 79.60.Ht – Disordered structures / 71.30.+h – Metal-insulator transitions
© EDP Sciences, 1996