Low-energy properties of the two-dimensional Hubbard model near half filling

Journal Article · Sun Oct 15 04:00:00 EDT 1995 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.52.11752· OSTI ID:122350

Friedman, B ^[1]; Levine, G ^[2]

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1. Department of Physics, Sam Houston State University, Huntsville, Texas 77341 (United States)
2. Department of Physics, Hofstra University, Hempstead, New York 11550 (United States)

In the first part of this paper we explore a configuration-interaction approach to the two-dimensional Hubbard model near half filling. To reproduce the result of degenerate second-order perturbation theory it is necessary to include Fock states having kinetic energy within 4{ital t} of the lowest kinetic-energy states. Using the ground state from the largest configuration-interaction calculation, we calculate the extended {ital s}- and {ital d}-wave superconducting correlation functions as a function of distance. There are indications of a nondecaying long-distance tail in the {ital d}-wave correlation function, that is, {ital d}-wave superconductivity in the ground state of the repulsive Hubbard model. In the second part of the paper, we reexamine our effective Hamiltonian for the repulsive Hubbard model near half filling. Simple considerations lead us to a more intuitively plausible form consistent with our previous results and spin-rotational invariance.

• OSTI ID: 122350
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 16 Vol. 52; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CLUSTER EXPANSION
CONFIGURATION INTERACTION
CORRELATION FUNCTIONS
D WAVES
HIGH-TC SUPERCONDUCTORS
HUBBARD MODEL
S WAVES
TWO-DIMENSIONAL CALCULATIONS