Mixed Rare Earth $({\rm Nd}_{1/3}{\rm Eu}_{1/3}{\rm Gd}_{1/3}){\rm Ba}_{2}{\rm Cu}_{3}{\rm O}_{7-{\rm d}}$ Thin Films by PLD for Coated Conductor

In order to investigate the possibility of using mixed rare earth (Nd_1/3Eu_1/3Gd_1/3)Ba₂Cu₃O_7-x (NEG123) as the superconducting layer of the HTS coated conductor, the NEG123 thin film was deposited epitaxially on LAO(100) single crystal and IBAD_YSZ metal templates by pulsed laser deposition. Systematic studies were carried out to investigate the influences of deposition parameters of PLD on the microstructure, texture and superconducting properties of NEG-123 coated conductor. Deposition at oxygen partial pressure of 600 mTorr was needed to routinely obtain high quality NEG123 films with J_C´s (77 K) over 2 MA/cm² and Tc´s over 90 K (DeltaT ~ 2 K) . We verified from magnetization study that the NEG123 has an improved in-field Jc as the field increases at temperatures between 10 K and 77 K compared with Gd123. The J_C (77 K, self field) and the value of onset T_C of NEG123 thin film on LAO substrate was 4.0 MA/cm² and 92 K, respectively. This is the first report, to the best of our knowledge, of coated conductors with NEG123 film as the superconducting layer which have Ic and Jc over 40 A/cm-width and 1.6 MA/cm² at 77 K, self field. This study shows the possibility of using NEG123 film as the superconducting layer of the HTS coated conductor which can be used in high magnetic field power electric devices.