Enhanced flux pinning properties of NaNbO3 nanorods added YBCO composite superconductor

Abstract

In this work, sodium niobate (NaNbO3) nanorods (NR) – YBCO superconductor composites with different wt% (0–2%) of NaNbO3 were prepared via a two-step process of hydrothermal and solid-state reaction, and its structural, electrical, and magnetic characterizations were carried out. XRD studies revealed that the orthorhombicity of YBCO is preserved in all nanocomposite samples. The superconducting transition temperature decreases from 92 K to 90.5 K when the addition of NaNbO3 was increased to 2 wt%. Magnetization studies revealed a significant increase of critical current (Jc) and pinning force (Fp) in the NaNbO3 (NR) added YBCO sample which has been attributed to the creation of artificial pinning centers due to the presence of NaNbO3 NR. For the 0.5 wt% nanorods added sample, the enhancement in Jc and Fp was maximum. Temperature and field dependence of Jc were carried out to probe the nature of pinning in the nanocomposite superconductors.