Superconducting transition in polycrystalline YBa2Cu3O7-x: diving into the meaning of Tc and the excess of electrical conductivity in the normal state

Abstract

Superconductivity is the property of certain materials to conduct direct current electricity without energy loss when they are cooled below a critical temperature 𝑇𝑐. The transition at this temperature is driven by thermal fluctuations, so deciding the exact value of 𝑇𝑐 is not a trivial matter. In this work we show different methods that have been used to estimate this temperature and deepen our understanding of the excess conductivity due to fluctuations. We can detect the mean-field, fluctuations, and full critical regions as they change with temperature