Large-[ital U] expansions for the Hubbard model at [ital T]=0. II

Journal Article · Wed Sep 01 04:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.6210· OSTI ID:6242086

Oitmaa, J; Jie, Yang; Henderson, J A; Weihong, Zheng ^[1]

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1. School of Physics, The University of New South Wales, Kensington, New South Wales 2033 (Australia)

We investigate the ground state of the Hubbard model in one and two dimensions. Long perturbation expansions in [ital t]/[ital U], i.e., about the atomic limit, are computed for the ground-state energy of finite lattices with [ital N][le]10 for arbitrary electron density. We also extend the series for the one-dimensional infinite lattice by expanding the Bethe-ansatz equations. Pade-approximant analysis of the series shows a distribution of singularities that varies dramatically with the electron density [ital n]. We also investigate the effect of inclusion of next-nearest-neighbor hopping. This appears to have little effect at half-filling but is significant away from half-filling.

• OSTI ID: 6242086
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:9; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665400* -- Quantum Physics Aspects of Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CRYSTAL MODELS
ENERGY LEVELS
GROUND STATES
HUBBARD MODEL
MATHEMATICAL MODELS
ONE-DIMENSIONAL CALCULATIONS
PADE APPROXIMATION
PERTURBATION THEORY
SERIES EXPANSION
TEMPERATURE ZERO K
TWO-DIMENSIONAL CALCULATIONS