${\rm GdBa}_{2}{\rm Cu}_{3}{\rm O}_{7-\delta }$ Coated Conductor on ${\rm BaZrO}_{3}$ -Buff

We report a successful fabrication of GdBa₂Cu₃O_7-delta (GdBCO) coated conductor on the ion-beam assisted deposition (IBAD) MgO template with a new buffer layer of BaZrO₃ (BZO). The BZO films were deposited on the IBAD-MgO template at various substrate temperatures (T _S) and oxygen partial pressures (PO₂) by pulsed laser deposition (PLD). In the broad ranges of T _S and PO₂, all BZO layers showed almost uniform in-plane texture (Deltaphi of ~ 6^deg ), implying that BZO is an attractive buffer layer. The surface roughness of BZO layer was sensitive to PO₂ but not to T _S. On the optimally processed BZO buffer layer with 5.1 nm RMS roughness, GdBCO coated conductor deposited at T _S of 750^degC and PO₂ of 400 mTorr exhibited Deltaphi of 4.4^deg , T _c,zero of 90.3 K, and J _c of 1.35 MA/cm² (77 K, self-field).