Exact solutions of frustrated ordinary and chiral eight-site Hubbard models

Journal Article · Mon Jul 15 04:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.44.1458· OSTI ID:5265284

Freericks, J K; Falicov, L M ^[1]; Rokhsar, D S ^[2]

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1. Department of Physics, University of California, Berkeley, CA (USA) Materials Science Division, Lawrence Berkeley Laboratory, Berkeley, CA (USA)
2. Department of Physics, University of California, Berkeley, CA (USA)

This contribution addresses the question of whether or not the ground state of a frustrated spin-1/2 Heisenberg model can be smoothly related to the ground state of a simple tight-binding model at half-filling in an appropriately chosen magnetic field. This continuity is considered explicitly for an eight-site square-lattice Hubbard model with nearest- and next-nearest-neighbor hopping, which approaches a frustrated Heisenberg model with nearest- and next-nearest-neighbor antiferromagnetic exchange coupling in the limit of large Hubbard {ital U}. In addition, a counterexample to the widely held belief that the half-filled band of the ordinary Hubbard model is nonmagnetic has been found in the regime where the hopping parameters and Hubbard interaction are all the same order of magnitude.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5265284
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 44:4; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

656100* -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANTIFERROMAGNETISM
CRYSTAL MODELS
HEISENBERG MODEL
HIGH-TC SUPERCONDUCTORS
MAGNETISM
MATHEMATICAL MODELS
SPIN EXCHANGE
SUPERCONDUCTORS