Improvement of uniformity of I_c distributions in long REBCO with BMO coated conductors by in-plume PLD method

Long REBa₂Cu₃O_X (REBCO, RE: rare earth element) with BaMO₃ (BMO, M: metal) coated conductors have been expected for the industrial and commercial applications at high temperatures in magnetic fields. Especially, the multi-filamentary structure long REBCO with BHO coated conductors are effective for control of the shielding current of coated conductor excited by applied magnetic fields and alternating-current loss. We fabricated long EuBa₂Cu₃O_X (EuBCO) with BaHfO₃ (BHO) coated conductors by the IBAD/PLD (conventional PLD) method, which showed the high in-field I_c values. However, in order to realize REBCO with BMO coated conductors for industrial and commercial applications, the much higher uniformity of not only longitudinal and but transversal I_c distributions of long coated conductors with high in-field performance is required. We have tried to develop the long EuBCO with BHO coated conductors by the in-plume (plane-plume) PLD method with high deposition rate of about 24 nm/s to obtain high in-filed performance and low production cost. More recently, we fabricated the 105 m long EuBCO with BHO coated conductors with high uniformity of longitudinal I_c distributions of 2.54 % (STDEV) by the in-plume (plane-plume) PLD method comparing with coated conductors by the conventional PLD method. We measured each I_c value of 8 filaments of 581 µm in width and slot of 20 µm in width for 0.6 m long EuBCO with BHO coated conductors by in-plume (plane-plume) PLD method. I_c distribution in a width direction of the EuBCO with BHO coated conductors by in-plume (plane-plume) PLD method is more uniform than that of the conventional PLD method.