Growth of a high performance SmBCO bulk superconductor with the addition of aSm2Ba4Cu2O9 phase

Abstract

By adding a novel Ba-rich Sm2Ba4Cu2O9 (Sm242) compound in the precursor material high performanceSmBa2Cu3O7 (Sm123or SmBCO) bulk superconductors were successfully grown in air by melt-textured (MT) growth. Highly-c-orientedSmBCO and NdBa2Cu3O7 (Nd123 or NdBCO) thin films with a superheating property were effectively utilized as seeds toinduce an epitaxy nucleation and growth. A primary study on the effect of the Sm242 additionon superconducting properties was carried out, proving that the critical transition temperature(Tc) can be substantially improved. It was found that, with the addition of 10 mol% Sm242, a highTc of over 94 K with asharp transition (ΔTc less than 1 K) can be achieved in the air-processed Sm123 bulk. A relatively strong peak effect in theJc–H curve is present at the intermediate field range, which might be attributed to the formationof a compositional fluctuation within the Sm123 matrix. An improvement in theparticle size and distribution of Sm211 in the Sm123 matrix was also observed.