Flavours of intrinsic d-wave induced effects in YBa₂Cu ₃O_7-δ grain boundary Josephson junctions

The quality of YBa2Cu3O7-δ biepitaxial grain boundary Josephson junctions has been improved and "tunnel-like" characteristics are reproducibly obtained. The consequent low barrier transmission probabilities is apparently favourable to isolate intrinsic d-wave induced effects. Extrinsic and intrinsic d-wave effects are discussed within the framework of novel designs for π-circuitry and qubits.