Single-particle excitations in narrow energy bands
- 7 July 1974
- journal article
- Published by IOP Publishing in Journal of Physics C: Solid State Physics
- Vol. 7 (13), 2269-2282
- https://doi.org/10.1088/0022-3719/7/13/007
Abstract
The Hubbard hamiltonian is analysed by means of Gutzwiller's variational scheme for both the nondegenerate and the degenerate band models. The single-particle excitations in the correlated ground state, which is determined by a balance between the electron hopping energy and the intra-atomic interaction energy, are investigated for arbitrary electron density and arbitrary correlation strength. It is found that the single-particle excitation energies forming a quasi-energy band. The centre of gravity of the quasi band is shifted from that of the bare band, and the bulk part of the density of states function for the quasi particles is narrowed by the correlation effect. Both the shift and the narrowing are spin-dependent. In the limit of strong correlation, our results agree with those obtained by Harris and Lange (1967) and Roth (1969).Keywords
This publication has 15 references indexed in Scilit:
- Metal-insulator transitions and Hund's rule coupling in degenerate narrow bandsJournal of Physics C: Solid State Physics, 1974
- Effect of Electron Correlation in a Narrow BandPhysical Review B, 1973
- Magnetic Transitions in a Degenerate BandPhysical Review B, 1971
- Correlation of Electrons in a Degenerate BandJournal of Applied Physics, 1971
- Single-Particle Excitations in Narrow Energy BandsPhysical Review B, 1967
- Correlation of Electrons in a NarrowBandPhysical Review B, 1965
- Electron correlations in narrow energy bands III. An improved solutionProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1964
- Electron correlations in narrow energy bandsProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1963
- Electron Correlation and Ferromagnetism of Transition MetalsProgress of Theoretical Physics, 1963
- Effect of Correlation on the Ferromagnetism of Transition MetalsPhysical Review Letters, 1963