Current dependent fluctuations in a Bi<Subscript>2</Subscript>Sr<Subscript>2</Subscript>CuO<Subscript>6+δ</Subscript> thin film

The current dependence of the excess conductivity is measured up to ≃3T<Subscript>c</Subscript> for a Bi<Subscript>2</Subscript>Sr<Subscript>2</Subscript>CuO<Subscript>6+δ</Sub script> thin film, as a function of doping. It is found to be anomalously sensitive to the transport current and to behave as a universal function of T/T<Subscript>c</Subscript> in the whole doping range. We discuss these results in the perspective of a granular superconductor with a gapless-like behavior. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2005