Influence of the structural anisotropy and of the order parameter symmetry on the transport properties of YBa<f>2</f>Cu<f>3</f>O<f>7−δ</f> grain boundaries Josephson junctions

YBa<f>2</f>C<f>3</f>O<f>7−δ</f> artificial grain boundary Josephson junctions have been fabricated by a recently implemented biepitaxial technique, employing MgO and CeO<f>2</f> as seed layers. The Josephson properties of asymmetric grain boundaries (GBs) characterised by a misalignment of the c-axis (45<f>°</f> c-axis tilt or twist) are presented. A comparison with GBs characterised by 45<f>°</f> c-axis tilt or twist and by an additional rotation of 45<f>°</f> of the a–b planes of one electrode has been also performed. The differences observed in the transport properties have been interpreted in terms of <f>dx2−y2</f> wave symmetry of the order parameter and faceting of the grain boundary. [Copyright &y& Elsevier]