Spectral Properties and Stability in the Two-Dimensional Lattice-Hubbard Model

The two-dimensional Hubbard model on the square lattice is studied in the presence of lattice distortions in the adiabatic approximation. The self energy is computed within perturbation theory up to second order, which provides a way for studying the quasiparticle dispersion. We compute numerically...

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Detalles Bibliográficos
Autor principal: Lamas, Carlos Alberto
Formato: Articulo Preprint
Lenguaje:Español
Publicado: 2009
Materias:
Ciencias Exactas
Física
lattice fermion models
phonon-electron interaction
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/38972
http://arxiv.org/abs/0708.4344
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-38972
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Español
topic Ciencias Exactas
Física
lattice fermion models
phonon-electron interaction
spellingShingle Ciencias Exactas
Física
lattice fermion models
phonon-electron interaction
Lamas, Carlos Alberto
Spectral Properties and Stability in the Two-Dimensional Lattice-Hubbard Model
topic_facet Ciencias Exactas
Física
lattice fermion models
phonon-electron interaction
description The two-dimensional Hubbard model on the square lattice is studied in the presence of lattice distortions in the adiabatic approximation. The self energy is computed within perturbation theory up to second order, which provides a way for studying the quasiparticle dispersion. We compute numerically the second order contribution to the self-energy using a standard fast Fourier transform algorithm for finite sizes system. The stability of the lattice distortions is investigated and a schematic phase diagram is drawn. The Fermi surface is analyzed for densities close to half filling, the presence of lattice distortions changes some spectral properties of the model and gives an anisotropic interacting Fermi surface. The spectral function is calculated along several lines in momentum space and the renormalized quasiparticle dispersion is obtained. The behavior of the density of states is shown for different values of the intrasite repulsion U in the different phases.
format Articulo
Preprint
author Lamas, Carlos Alberto
author_facet Lamas, Carlos Alberto
author_sort Lamas, Carlos Alberto
title Spectral Properties and Stability in the Two-Dimensional Lattice-Hubbard Model
title_short Spectral Properties and Stability in the Two-Dimensional Lattice-Hubbard Model
title_full Spectral Properties and Stability in the Two-Dimensional Lattice-Hubbard Model
title_fullStr Spectral Properties and Stability in the Two-Dimensional Lattice-Hubbard Model
title_full_unstemmed Spectral Properties and Stability in the Two-Dimensional Lattice-Hubbard Model
title_sort spectral properties and stability in the two-dimensional lattice-hubbard model
publishDate 2009
url http://sedici.unlp.edu.ar/handle/10915/38972
http://arxiv.org/abs/0708.4344
work_keys_str_mv AT lamascarlosalberto spectralpropertiesandstabilityinthetwodimensionallatticehubbardmodel
bdutipo_str Repositorios
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