Realization of a Thin Film High-Tc π-SQUID

The predominantly dx2−y2 symmetry of the order parameter in most high-Tc superconductors provides the opportunity to construct novel Josephson junction circuits, in which part of the junctions are biased with a phase-difference of π. We present fabrication and measurements of an all high-Tc dc π superconducting quantum interference device (dc π-SQUID), realized in thin film technology on a tetracrystalline substrate [1]. This device contains a standard junction and a junction with a π-phase shift. The characteristics of the π-SQUID are compared with the properties of a standard high-Tc SQUID. The unique features of the π-SQUID offer important potential for applications. This work was supported by the BMBF (project number 13N6918/1).