The superconducting transition and the behavior of the ac susceptibility

The ac susceptibility behavior of superconductors close to the superconducting transition temperature is explained on the basis of the BCS theory. Previous approaches to this problem were based on the average conductivity model, the London and the two-fluid models. It is shown that they are not able to explain the observed χPrime;-peak at T_c and are basically, not adequate for the treatment of such a problem.