New substrate PrGaO3 for a high T c superconducting YBa2Cu3Ox epitaxial film

The potential of a new substrate, PrGaO3, for high Tc oxide superconducting films is investigated and results indicate it is the most suitable material studied so far. Single crystals were grown by the Czochralski method. The lattice mismatch between PrGaO3 and YBa2Cu3Ox superconductor was estimated to be only 0.02% at the elevated deposition temperature. The dielectric constant value was 24 at 10 kHz. The c-axis oriented YBa2Cu3Ox films were deposited onto PrGaO3 substrates by the laser ablation technique. Their superconducting transition temperature was as high as 90 K, even for a film thickness of only 500 Å.