Laser-deposited PrGaO3 films on SrTiO3 substrates and in YBa2Cu3O7/PrGaO3/YBa2Cu3O7 trilayers

PrGaO3 films were successfully grown by laser deposition at temperatures between 730 and 785 °C. The minimum full width at half maximum value of the (004) x-ray diffraction peak was 0.14°, for films deposited on SrTiO3 substrates at 760 °C. The optimum temperature for deposition of PrGaO3 in YBa2Cu3O7/PrGaO3/YBa2Cu3O7 trilayers was found to be 760 °C. Three distinct layers were observed, and the PrGaO3 exhibited two orientations with respect to the c-axis oriented bottom layer; either the [001] or the [110] direction parallel to the YBa2Cu3O7 c axis. Two orthogonal in-plane orientations were observed for each of these cases. The highest resistivity (at 100 K) of the PrGaO3 layer was 105 Ω cm. Considerable interaction occurred between the PrGaO3 and the YBa2Cu3O7 bottom layer at 785 °C, where the two bottom layers deteriorated.