Development of In-Plume Pulsed Laser Deposition of High-Ic GdBCO Films for Coated Conductors

We studied a feasibility of pulsed laser deposition technique (PLD) for high-rate deposition of high-Ic GdBa₂Cu₃O_y based films (GdBCO) with improved flux pinning characteristics. It was found that in-plume deposition (IP-PLD) of off-stoichiometric Ba-poor films at a high laser energy density combined with addition of BaZrO₃ (BZO) is very helpful for suppression of critical current density (Jc) degradation vs film thickness. Very high Ic at 77.5 K in a range of 700-1000 A/cm was estimated in a self-field for short GdBCO samples deposited on Hastelloy/Gd₂Zr₂O₇/CeO₂ substrates. The record high Ic of 135 A/cm in the magnetic field of 3 Tesla applied perpendicular to the film surface and minimal value of 100 A/cm in angular dependent I_c measurements were achieved on single-layer 5 microns thick GdBCO+BZO film.