First observation for a cuprate superconductor of fluctuation-induced diamagnetism well inside the finite-magnetic-field regime

For the first time for a cuprate superconductor, measurements performed abo ve T-c in high quality grain aligned La1.9Sr0.1CuO4 samples have allowed th e observation of the thermal fluctuation induced diamagnetism well inside t he finite-magnetic-field fluctuation regime. These results may be explained in terms of the Gaussian Ginzburg-Landau approach for layered superconduct ors, but only if the finite field contributions are estimated by taking off the short-wavelength fluctuations.