Inhomogeneity of the superconducting state and consequent diamagnetism above Tc: Application to the cuprates

The inhomogeneity of a superconducting system gives rise to an interesting situation when at T>T^res_c (T^res_c is characterized by a relatively sharp resistive transition) one can observe an anomalously large diamagnetic moment. Here we focus on the case when the sample can be described as containing a nonuniform distribution of magnetic impurities and, as a consequence, by an inhomogeneous distribution of critical temperatures. The analysis is in good agreement with experimental data on overdoped cuprates.