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Title: Cluster expansion for the self-energy: A simple many-body method for interpreting the photoemission spectra of correlated Fermi systems

Abstract

The self-energy of a translational invariant system of interacting fermions may be expanded in diagrams contributing to the self-energy of finite clusters with open boundary conditions. The exact solution of small clusters might therefore be used to construct a systematic approximation to the self-energy of the infinite system. This approximation incorporates both the local and the itinerant degrees of freedom on an equal footing. We develop this method for the one-band Hubbard Hamiltonian and apply it to the three-band Hamiltonian of the CuO superconductors. Already the lowest nontrivial approximation yields interesting results for the spectral density useful for the interpretation of photoemission experiments. We find (i) transfer of spectral weight from the upper to the lower Hubbard band upon doping, (ii) the formation of an [ital isolated] band of Zhang-Rice singlets separated from the band of triplet states by a many-body gap, and (iii) creation of density of states [ital above] the top of the oxygen band upon doping.

Authors:
;  [1]
  1. Institut fuer Physik, Universitaet Dortmund, Postfach 500 500, 4600 Dortmund 50 (Germany)
Publication Date:
OSTI Identifier:
5654297
Resource Type:
Journal Article
Journal Name:
Physical Review, B: Condensed Matter; (United States)
Additional Journal Information:
Journal Volume: 48:1; Journal ID: ISSN 0163-1829
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COPPER OXIDES; CLUSTER EXPANSION; PHOTOEMISSION; HIGH-TC SUPERCONDUCTORS; CORRELATED-PARTICLE MODELS; CRYSTAL DOPING; FERMI STATISTICS; HUBBARD MODEL; SELF-ENERGY; CHALCOGENIDES; COPPER COMPOUNDS; CRYSTAL MODELS; EMISSION; ENERGY; MATHEMATICAL MODELS; OXIDES; OXYGEN COMPOUNDS; PARTICLE MODELS; SECONDARY EMISSION; SERIES EXPANSION; SUPERCONDUCTORS; TRANSITION ELEMENT COMPOUNDS; 360207* - Ceramics, Cermets, & Refractories- Superconducting Properties- (1992-)

Citation Formats

Gros, C, and Valenti, R. Cluster expansion for the self-energy: A simple many-body method for interpreting the photoemission spectra of correlated Fermi systems. United States: N. p., 1993. Web. doi:10.1103/PhysRevB.48.418.
Gros, C, & Valenti, R. Cluster expansion for the self-energy: A simple many-body method for interpreting the photoemission spectra of correlated Fermi systems. United States. https://doi.org/10.1103/PhysRevB.48.418
Gros, C, and Valenti, R. Thu . "Cluster expansion for the self-energy: A simple many-body method for interpreting the photoemission spectra of correlated Fermi systems". United States. https://doi.org/10.1103/PhysRevB.48.418.
@article{osti_5654297,
title = {Cluster expansion for the self-energy: A simple many-body method for interpreting the photoemission spectra of correlated Fermi systems},
author = {Gros, C and Valenti, R},
abstractNote = {The self-energy of a translational invariant system of interacting fermions may be expanded in diagrams contributing to the self-energy of finite clusters with open boundary conditions. The exact solution of small clusters might therefore be used to construct a systematic approximation to the self-energy of the infinite system. This approximation incorporates both the local and the itinerant degrees of freedom on an equal footing. We develop this method for the one-band Hubbard Hamiltonian and apply it to the three-band Hamiltonian of the CuO superconductors. Already the lowest nontrivial approximation yields interesting results for the spectral density useful for the interpretation of photoemission experiments. We find (i) transfer of spectral weight from the upper to the lower Hubbard band upon doping, (ii) the formation of an [ital isolated] band of Zhang-Rice singlets separated from the band of triplet states by a many-body gap, and (iii) creation of density of states [ital above] the top of the oxygen band upon doping.},
doi = {10.1103/PhysRevB.48.418},
url = {https://www.osti.gov/biblio/5654297}, journal = {Physical Review, B: Condensed Matter; (United States)},
issn = {0163-1829},
number = ,
volume = 48:1,
place = {United States},
year = {1993},
month = {7}
}