https://doi.org/10.1007/s100510070054
Anisotropy of the energy gap in the insulating phase of the U-t-t' Hubbard model
Institut für Physik, Theoretische Physik III, Elektronische Korrelationen und Magnetismus, Universität Augsburg,
86135 Augsburg, Germany
Received:
18
May
2000
Revised:
9
August
2000
Published online: 15 November 2000
We apply a diagrammatic expansion method around the atomic limit
() for the U-t-t' Hubbard model at half filling and finite
temperature by means of a continued fraction representation of the
one-particle Green's function. From the analysis of the spectral function
we find an energy dispersion relation with a
modulation of the energy gap in the insulating phase.
This anisotropy is compared with experimental ARPES results on insulating
cuprates.
PACS: 71.10.Fd – Lattice fermion models (Hubbard model, etc.) / 71.27.+a – Strongly correlated electron systems; heavy fermions / 71.30.+h – Metal-insulator transitions and other electronic transitions
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000