Antiferromagnetism in three-band Hubbard model: Local-ansatz approach

Journal Article · Fri Mar 01 00:00:00 EST 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.5622· OSTI ID:5885516

Dutka, J; Oles, A M ^[1]

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1. Institute of Physics, Jagellonian University, Reymonta 4, PL-30-059 Krakow, Poland (PL)

The ground state of the three-band Hubbard Hamiltonian for CuO{sub 2} planes of high-{ital T}{sub {ital c}} superconductors is investigated. Correlations between holes are included by a local-ansatz approach which starts from the Hartree-Fock approximation and emphasizes the local character of hole correlations. It is found that the hole distribution within CuO{sub 2} planes and the region of stability of an antiferromagnetic (AF) ground state are significantly modified by hole correlations. At the filling of one hole per CuO{sub 2} unit, and for realistic parameters, the ground state exhibits an AF long-range order. Taking into account the effect of quantum fluctuations, the magnetic moment amounts to 0.47{mu}{sub {ital B}} which agrees very well with the experimental value for La{sub 2}CuO{sub 4}. The order parameter decreases with doping and disappears for the doping of 0.06 hole per unit cell. It is found that the nearest-neighbor oxygen hopping destabilizes AF ground state which proves the importance of this parameter for quantitative analysis. A favorable comparison between the present results and those obtained within variational Monte Carlo, as well as within the Gutzwiller approximation for a similar model, is presented.

• OSTI ID: 5885516
• Journal Information: Physical Review, B: Condensed Matter; (USA), Vol. 43:7; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HIGH-TC SUPERCONDUCTORS
ANTIFERROMAGNETISM
BAND THEORY
COPPER OXIDES
GROUND STATES
HOLES
LANTHANUM OXIDES
MONTE CARLO METHOD
ORDER PARAMETERS
CHALCOGENIDES
COPPER COMPOUNDS
ENERGY LEVELS
LANTHANUM COMPOUNDS
MAGNETISM
OXIDES
OXYGEN COMPOUNDS
RARE EARTH COMPOUNDS
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