SPIN FLUCTUATION SPECTRA AND HIGH-TEMPERATURE SUPERCONDUCTIVITY

The spin fluctuation mechanism for the high temperature superconductivity in cuprates is investigated with a parametrization of the spin fluctuation spectra in terms of the self-consistent renormalization theory of spin fluctuations. The doping concentration dependence of the transition temperature in the best studied cuprates is explained in terms of the parameter values estimated from the normal state experiments. We find that the larger the amplitude and the energy spread of spin fluctuations, the higher T(c). In this context the cuprates have much favorable properties compared with some other antiferromagnetic spin fluctuation systems whose parameter values are estimated for comparison.