Microstructures and Enhancement of Critical Current Density in$rm YBa_2rm Cu_3rm O_7$Thin Films Grown by Pulsed Laser Deposition on Various Single Crystal Substrates Modified by Ag Nano-Dots
- Citation data:
IEEE Transactions on Appiled Superconductivity, ISSN: 1051-8223, Vol: 15, Issue: 2, Page: 3046-3049
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- Repository URL:
- https://works.bepress.com/xlwang/43; https://ro.uow.edu.au/engpapers/59; https://works.bepress.com/sxdou/39; https://works.bepress.com/hkliu/56
- Materials Science; Physics and Astronomy; Engineering
YBaCuO(Y123) thin films were grown by pulsed laser deposition (PLD) on YSZ (100), SrTiO3 (100), and LaAlO3 (100) single crystal substrates. Prior to the film deposition, a discontinuous layer of Ag nano-dots was deposited on the substrates. The Y123 films grown on such surfaces modified with Ag nano-dots were characterized by Atomic Force Microscopy (AFM), X-ray diffraction (XRD), scanning electron microscopy (SEM), AC susceptibility and DC magnetization. The effects of the density of Ag nano-dots, which was controlled by the numbers of PLD shots, on the microstructures and resultant critical current density Jhave been studied systematically. Results showed that at fixed physical deposition conditions Jincreased monotonically with number of Ag shots, n, for films grown on both STO and LAO substrates. At 77 K, the Jincreased from 10to 3.2 × 10A/cmfor LAO and from 8 × 10to 3.5 × 106 A/cmfor STO as n increased from 0 to 150. At 5 K, the enhancement of Jwas approximately four times at both low and high fields. However, for films grown on YSZ substrate, Jincreased from 2 × 10to 2 × 10A/cmas Ag shots increased from 0 to 30, and decreased to 9 × 10for n ≥ 60. Detailed microstructure investigations indicated that the crystallinity and ab alignment gradually improved as the number of Ag-nano-dots increased. © 2005 IEEE.