Microstructural Characterization of BaSnO₃ Pinning Center in GdBa₂Cu₃O_y Film

Abstract

BaSnO₃ (BSO) doped GdBa₂Cu₃O_y (GdBCO) films were deposited on CeO₂ (200) substrates using the pulsed laser deposition (PLD) method. Both 2D and 3D microstructural characterization were carried out by transmission electron microscope with selected area electron diffraction patterns, scanning transmission electron microscope with energy dispersive X-ray spectroscopy and electron tomography. In the GdBCO film with BSO 7.5 mol% addition, BSO nanorods were observed with an average width of 8.7 nm, average length of 43 nm, volume fraction of 3.4%, and number density of 2.7×10¹⁶ cm^-3. Additionally, BSO nanorods were grown in the film with the tilted angle of approximately 0-30 degrees to the c-axis direction of GdBCO. Improvements of J_c were clearly due to the presence of these BSO nanorods.