Self-fields in thin superconducting tapes: Implications for the thickness effect in coated conductors

A large decrease in transport current density has been observed in high-temperature superconducting films for increasing film thickness. In this work we theoretically explain the nature and the ubiquitous presence of this so-called thickness effect by analyzing the self-field created by the transport currents in the superconductor, assuming a realistic field-dependent critical-current density Jc. This knowledge can help in finding ways to improve transport current in superconducting films.