Self-consistent calculation of spin fluctuations for the two-dimensional Hubbard model and additional high-{ital T}{sub {ital c}} pairing interaction

Journal Article · Tue Mar 01 04:00:00 EST 1994 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.49.6869· OSTI ID:142615

Wermbter, S ^[1]

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1. Institut fuer Theoretische Physik, Universitaet Bremen, Postfach 300440, D-28 334 Bremen (Germany)

The momentum, energy, and temperature dependence of the dynamic spin susceptibility is calculated self-consistently for the two-dimensional Hubbard model with additional electron-phonon interaction. The spin-fluctuation spectral density considered as a function of momentum exhibits four incommensurate peaks and a local minimum at the zone edge of the Brillouin zone. The large self-energy corrections tend to smooth out the peak and gap structure of the spin fluctuation spectral density. In the presence of an electron-phonon interaction ({lambda}{sub ph}{sup eff}{approx}2.2,{ital U}/{ital t}=2.3) a transition temperature {ital T}{sub {ital c}}=84 K is found for {ital s}-wave pairing. Above {ital T}{sub {ital c}} the incommensurate peak and gap structure seen in a momentum scan is strongly smoothed out, and for increasing temperature and energy, the two well-separated peaks evolve into a single broad peak at the zone edge. For lower energies the whole structure is rapidly suppressed as the temperature drops below {ital T}{sub {ital c}}. The results for the resistivity, the nuclear-spin relaxation rate, and the neutron-scattering spectral weight are compared with experimental data on La{sub 2{minus}{ital x}}Sr{sub {ital x}}CuO{sub 4} and YBa{sub 2}Cu{sub 3}O{sub 7{minus}{ital x}}.

• OSTI ID: 142615
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 10 Vol. 49; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ELECTRON-PHONON COUPLING
ENERGY DEPENDENCE
FREQUENCY DEPENDENCE
HIGH-TC SUPERCONDUCTORS
HUBBARD MODEL
MAGNETIC SUSCEPTIBILITY
PAIRING INTERACTIONS
SELF-CONSISTENT FIELD
TEMPERATURE DEPENDENCE
TWO-DIMENSIONAL CALCULATIONS