Superconductivity, phase separation, and charge-transfer instability in the U = infinity limit of the three-band model of the CuO sub 2 planes

Journal Article · Mon Jul 08 00:00:00 EDT 1991 · Physical Review Letters; (USA)

DOI:https://doi.org/10.1103/PhysRevLett.67.259· OSTI ID:5461485

Grilli, M; Raimondi, R; Castellani, C; Di Castro, C ^[1]; Kotliar, G ^[2]

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1. Dipartimento di Fisica, Universita di Roma La Sapienza,'' I-00185 Roma, Italy (IT)
2. Serin Physics Laboratory, Rutgers University, P.O. Box 849, Piscataway, New Jersey 08854 (USA)

The {ital U}={infinity} limit of the three-band Hubbard model with nearest-neighbor repulsion {ital V} is studied using the slave-boson approach and the large-{ital N} expansion technique to order 1/{ital N}. A charge-transfer instability is found as in weak-coupling theory. The charge-transfer instability is always associated with a diverging compressibility leading to a phase separation. Near the phase-separation, charge-transfer-instability region we find superconducting instabilities in the {ital s}- and {ital d}-wave channel. The requirement for superconductivity is that {ital V} be on the scale of the Cu-O hopping as suggested by Varma, Schmitt-Rink, and Abrahams.

• OSTI ID: 5461485
• Journal Information: Physical Review Letters; (USA), Vol. 67:2; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HIGH-TC SUPERCONDUCTORS
BAND THEORY
COPPER OXIDES
HYBRIDIZATION
INSTABILITY
PAIRING INTERACTIONS
QUASI PARTICLES
CHALCOGENIDES
COPPER COMPOUNDS
INTERACTIONS
OXIDES
OXYGEN COMPOUNDS
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
656100* - Condensed Matter Physics- Superconductivity