Scaling Behavior of YBaCuO/PrBaCuO/YBaCuO Trilayer Josephson Junctions

We have fabricated Josephson junctions consisting of all (103)-oriented YBaCuO/PrBaCuO/YBaCuO trilayer films, varying the thickness of the PrBaCuO barrier from 45 to 100 nm and the junction area from 10×10 to 50×50 µm2. A scaling behavior with critical current× normal resistance ( I c R n products) proportional to (critical current density J c)1/2 is observed for fabricated trilayer junctions. Furthermore, it is found that junctions with trilayer and edge structures reported by other groups also obey this scaling behavior, strongly suggesting that the junction properties can be determined by the lowered value of the order parameter at the interface between the YBaCuO film and barrier layer, due to the proximity effect within the framework of the short-coherence-length effect.