Growth of epitaxial Sr2RuO4 films and YBa2Cu3O7 − δSr2RuO4 heterostructures

Sr2RuO4 is the only known layered perovskite that is free of copper, yet superconducting. Its low metallic resistivity and excellent lattice match with YBa2Cu3O7 − δ make it an attractive candidate for use as conductive electrodes to YBa2Cu3O7 − δ-based superconducting devices or as a normal metal in YBa2Cu3O7 − δ-based SNS junctions. Single-domain a-axis oriented epitaxial films of Sr2RuO4 have been grown in situ by pulsed laser deposition on (1 0 0) LaSrGaO4 substrates. Single-domain c-axis oriented Sr2RuO4 films have been grown on (1 0 0) LaAlO3, (1 1 0) NdGaO3, and (1 0 0) SrTiO3 substrates. Heterostructures containing YBa2Cu3O7 − δ have also been grown. Resistivity versus temperature measurements reveal that the as-grown Sr2RuO4 films are metallic, but not superconducting.