Enhanced critical current density and pinning properties in KNbO3 nanoparticles added YBCO superconductor

In the present work, the effect of the addition of potassium niobate (KNbO3) nanoparticles (NPs) on the pinning properties of YBCO compound is investigated. The synthesis of YBCO:xKNbO(3) (x = 0-1 wt%) nanocomposites were carried out using a two-step process, firstly KNbO3 NPs were synthesized via hydrothermal process, and later on, the nanocomposites were synthesized via solid-state reaction method containing various concentrations of NPs from 0 to 1 wt%. The effect of NPs of KNbO3 in YBCO is studied using structural, morphological, transport, and magnetic measurements. From XRD spectra, the crystal structure of YBCO was found to be orthorhombic, which remained invariant even in the nanocomposites. Magnetic properties of YBCO and its nanocomposites over the range of - 6 T to + 6 T were characterized using magnetic property measurement system (MPMS). The Bean model is applied to calculate the critical current density (J(C)), which has improved in YBCO:KNbO3 nanocomposites as compared to YBCO. The maximum enhancement of similar to 4.4 times in J(C) and pinning properties was found for YBCO:0.5wt%KNbO3 nanocomposites due to the creation of defects in YBCO matrix. Additionally, it is observed that for nanocomposites compared to YBCO, the rate of J(C) decay decreases with an increase of externally applied field, which indicates an enhancement in pinning properties of nanocomposites.

Automated summary

This study investigates the effect of adding potassium niobate (KNbO3) nanoparticles (NPs) on the pinning properties of YBCO compound. YBCO:xKNbO(3) (x = 0-1 wt%) nanocomposites were synthesized via a two-step process. The addition of KNbO3 NPs improved the critical current density (J(C)) and pinning properties of YBCO, with the highest enhancement observed in YBCO:0.5wt%KNbO3 nanocomposites. Furthermore, the decay rate of J(C) decreased in the nanocomposites compared to YBCO, indicating enhanced pinning properties.