Growth and properties of NdBCO-Ag large grains for device applications

Nd1+xBa2-xCu3Oy (NdBCO) bulk materials are known to have superior supercond ucting properties than YBa2Cu3O7-delta (YBCO). However, several barriers ne ed to be overcome prior to the development of reliable fabrication techniqu es for these materials. One of these barriers is the required tight control of processing oxygen partial pressure p(O-2), which dictates the degree of Nd3+ substitution onto Ba2+-site and consequently affects both T-c and J(c ). In addition, it is difficult to find an appropriate seed with similar la ttice structure to and higher melting point than NdBCO, due to its nearly t he highest peritectic temperature in the REBCO series. This paper focuses o n establishing the growth conditions of Ag-doped, and hence melting point d epressed, NdBCO large grains under high p(O-2) of 1-5% using NdBCO seeds in troduced either at room temperature or near the peritectic temperature of N dBCO-Ag. The superconducting properties of the large NdBCO-Ag grains fabric ated following the optimized conditions were also characterized.