ANTIFERROMAGNETIC SPIN FLUCTUATIONS AND SUPERCONDUCTIVITY IN 2-DIMENSIONAL METALS - A POSSIBLE MODEL FOR HIGH-TC OXIDES

Spin fluctuations in antiferromagnetic and nearly antiferromagnetic two dimensional (square lattice) itinerant electron systems, as a possible model for high Tc superconductors, are investigated by using the self-consistent renormalization theory. The electrical resistivity and the nuclear spin relaxation rate due to the spin fluctuations in the normal state are calculated. The results in the nearly antiferromagnetic regime as applied to high Tc oxides seem to explain the experimental results both in their temperature dependence and in their orders of magnitudes. By using the same spin fluctuations we discuss superconductivity due to the spin fluctuation mechanism within a weak coupling theory. The order parameter is shown to have B1g or A2g symmetry and the critical temperature is evaluated to be of the right order of magnitude. © 1990, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.