Influence of d-wave order parameter fluctuations on spin fluctuations in underdoped high-Tc cuprates
Abteilung für Theoretische Festkörperphysik,
Universität Hamburg, Jungiusstr. 11, D-20355 Hamburg,
Accepted: 6 June 1997
We consider the effect of fluctuations of the superconducting -wave gap above Tc for the 2D Hubbard model. The order parameter fluctuations (OPFL) lead to a decrease of Tc and to a suppression of the dynamical spin susceptibility below a crossover temperature which can be much larger than Tc. The temperature increases while Tc decreases with increasing strength of OPFL, or decreasing doping. The resulting neutron scattering intensity and NMR relaxation rates decrease below for decreasing T. This agrees qualitatively with the observed spin gap behavior in the underdoped high-Tc cuprates.
PACS: 74.20.Mn – Nonconventional mechanisms (spin fluctuations, polarons and bipolarons, resonating valence bond model, anyon mechanism, marginal Fermi liquid, Luttinger liquid, etc.) / 74.40.+k – Fluctuations (noise, chaos, nonequilibrium superconductivity, localization, etc.) / 74.72.-h – High-Tc compounds
© EDP Sciences, 1997