Large electric field effects in YBa2Cu3O7−δ films containing weak links

The influence of applied electric fields on the transport properties of weak links in YBa2Cu3O7−δ films has been investigated. It is found that the critical temperature Tc0 of epitaxial films containing weak links can be reduced by 10 K with applied electric fields of 6 MV/cm. In one case, Tc0 shifts of up to 25–30 K were observed. These are by far the largest Tc shifts reported for any superconducting system.