Calculation of Coulomb-interaction parameters for La/sub 2/CuO/sub 4/ using a constrained-density-functional approach

Journal Article · Mon May 01 04:00:00 EDT 1989 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.39.9028· OSTI ID:6182592

Hybertsen, M S; Schlueter, M; Christensen, N E

The constrained-density-functional approach is used to calculate the energy surface as a function of local charge fluctuations in La/sub 2/CuO/sub 4/. This energy surface is then mapped onto a self-consistent mean-field solution of the Hubbard model which allows extraction of the Coulomb interaction parameters when combined with one-electron parameters derived from band-structure results. Variations in the local Cu d charges and in-plane O p charge are considered for the prototypical high-T/sub c/ parent oxide La/sub 2/CuO/sub 4/. To isolate the charge fluctuations, the calculations are done in a supercell of size up to 2 x 2 in the basal plane. The local density-functional calculations are done using the linear muffin-tin orbital approach with the atomic sphere approximation. In the Hubbard Hamiltonian, the Cu d(x/sup 2/-y/sup 2/) and O p(x,y) orbitals are included in the pdsigma configuration. The one-electron parameters consist of bare on-site energies (epsilon-c/sub p/,epsilon-c/sub d/) and first-neighbor hopping from Cu to O (t/sub p//sub d/) and from O to O (t/sub p//sub p/) while the Coulomb-interaction parameters include on-site (U/sub d/,U/sub p/) and intersite (U/sub p//sub d/,U/sub p//sub p/) terms. Results of the present calculation indicate that La/sub 2/CuO/sub 4/ is intermediate between the extreme spin or charge fluctuation regimes. This places strong constraints on the available parameter space for theories of high-T/sub c/ superconductivity based on the extended Hubbard model.

• Research Organization: ATandT Bell Laboratories, Murray Hill, New Jersey 07974
• OSTI ID: 6182592
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 39:13; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANGULAR MOMENTUM
BAND THEORY
CHALCOGENIDES
CHARGE DENSITY
COPPER COMPOUNDS
COPPER OXIDES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON-ELECTRON INTERACTIONS
FLUCTUATIONS
INTERACTIONS
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
LEPTON-LEPTON INTERACTIONS
MEAN-FIELD THEORY
OXIDES
OXYGEN COMPOUNDS
PARTICLE INTERACTIONS
PARTICLE PROPERTIES
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SPIN
SUPERCONDUCTIVITY
TRANSITION ELEMENT COMPOUNDS
VARIATIONS