Phase diagram of doped oxide superconductors: A slave-boson approach

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

DOI:https://doi.org/10.1103/PhysRevB.47.11540· OSTI ID:6642008

Riseborough, P S ^[1]; Hanggi, P ^[2]

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1. Department of Physics, Polytechnic University, Brooklyn, New York 11201 (United States)
2. Lehrstuhl fuer Theoretische Physik, Universitaet Augsburg, D8900 Augsburg (Germany)

A phase diagram for the doped high-temperature superconductors is calculated, using a tight-binding model for the electronic states in the copper oxide planes. The model includes the oxygen [ital p]([ital x]) and [ital p]([ital y]) orbitals and the copper 3[ital d]([ital x][sup 2][minus][ital y][sup 2]) orbitals. The hybridization between the copper [ital d]([ital x][sup 2][minus][ital y][sup 2]) and the oxygen [ital p]([ital x]) and [ital p]([ital y]) orbitals is considered, with the direct overlap between the [ital p] orbitals of neighboring oxygen ions. The Coulomb interaction is treated by the slave-boson mean-field theory. The system shows a phase diagram consisting of a highly correlated metal, for general values of the doping. For hole doping, there also exists a possible high-temperature state with completely localized [ital d] electrons. This occurs if the bare charge-transfer energy is sufficiently large. Thus, for the stoichiometric system there are two possible zero-temperature states; a metallic state and a charge-transfer insulator state. The introduction of the [ital p]-[ital p] hopping matrix element has a significant effect on the phase diagram. The paramagnetic phase of La[sub 2]CuO[sub 4] is found to be metallic. The mean-field theory does not include the effects of the antiferromagnetic ordering, that could open an antiferromagnetic Slater gap in the metallic system.

• DOE Contract Number: FG02-84ER45127
• OSTI ID: 6642008
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 47:17; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665411* -- Basic Superconductivity Studies-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BOSONS
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
DIAGRAMS
DOPED MATERIALS
ELECTRON TRANSFER
ELECTRONIC STRUCTURE
HIGH-TC SUPERCONDUCTORS
HOLES
HYBRIDIZATION
MAGNETIC PROPERTIES
MATERIALS
MEAN-FIELD THEORY
OXIDES
OXYGEN COMPOUNDS
PHASE DIAGRAMS
PHYSICAL PROPERTIES
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS