Accession Number : ADA119188

Title :   Correlation and Collective Modes in Narrow Band Materials.

Descriptive Note : Interim rept. 1 Oct 80-30 Sep 81,


Personal Author(s) : Ribarsky,Martin W

PDF Url : ADA119188

Report Date : 25 May 1982

Pagination or Media Count : 29

Abstract : Correlation and collective modes have been studied for systems with quite localized valence or conductive bands. In particular this research has been concerned with localized electron-hole states and how they contribute with other excitations to the dynamical response of the system. The most important aspect studied has been the effect of excitons or exciton-like states on superconducting properties. Initially the system studied has been Cu2O for which a simplified tight-binding model was used. The results showed that an effective attractive interaction between electrons due to the local field produced by interacting electron-hole pairs was possible. Under the appropriate conditions this interaction could lead to a superconducting state. The contribution of the localized excitation structure and plasmon modes to the electronic loss spectra was also analyzed. Here the effect of the primary electron energy on the plasmon peak position was shown to be significant. (Author)

Descriptors :   *Narrowband, *Materials, *Transition metals, Correlation techniques, Collection, Energy, Losses, Superconductivity, Copper, Oxides, Frequency bands, Excitation

Subject Categories : Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE