Self-consistent perturbation theory for dynamics of valence fluctuations |
| |
Authors: | H. Kojima Y. Kuramoto M. Tachiki |
| |
Affiliation: | (1) The Research Institute for Iron, Steel and Other Metals, Tohoku University, 980 Sendai, Japan;(2) Present address: Department of Applied Physics, Tohoku University, 980 Sendai, Japan |
| |
Abstract: | Dynamical as well as equilibrium properties of model Ce systems are investigated in both the intermediate-valence and nearly integral-valence (Kondo) regimes at finite temperatures. With self-consistent account of hybridization effects between the conduction bands and the highly correlated 4f states, the 4f-electron density of states4f() and the dynamical magnetic susceptibility () are derived. Equilibrium properties such as the static magnetic susceptibility and the averaged 4f-electron number are also computed within the same approximation scheme that neglects intersite interactions between different Ce ions. In the intermediate-valence regime the calculated line-shape of Im ()/ is close to the Lorentzian at high temperatures, but at low temperatures there appears an inelastic peak. In the Kondo regime it is shown that a sharp peak in4f() develops at the Fermi level as the temperature decreases. The line-shape of Im ()/ is shown to be close to the Lorentzian at all temperatures. The half-width is considerably enhanced over the Korringa value expected for the local-moment system. The temperature dependence of the half-width agrees qualitatively with experimental results in Kondo compounds such as CeB6, CeCu2Si2 and CeAl3. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|