Comparative Study between Similarly Processed YBa2Cu3O7-x Films with Y2BaCuO5 or BaSnO3 Additions (Postprint)
Abstract
A special YBa2Cu3O7-x (YBCO) target with a thin sector of second phase material, in this case either Y2BaCuO5 (Y211) or BaSnO3 (BSO), was used to deposit YBCO films with non-layered nanoparticles on single crystal LaAlO3 and biaxially textured Ni-5 at.% W substrates buffered with CeO2 and YSZ layers (coated conductors). Although identical processing conditions were used, TEM images indicated that random Y211 nanoparticles in the case of YBCO+Y211, and evenly spaced BSO nanocolumns in the case of YBCO+BSO, form in the YBCO films. While YBCO plane buckling was observed at many places in the case of YBCO+Y211, a high density of stacking faults and dislocations were observed in the case of YBCO+BSO near the BSO columns. In transport critical current density (J(sub c)) angular dependence measurements, the absence of nanocolumns in YBCO+Y211 films resulted in the absence of a peak at 0 degrees, J(sub c) (H//c), in J(sub c) vs theta plots, as compared to a clear peak at 0 degrees observed in YBCO+BSO films with the nanocolumns. The in-field J(sub c) measurements indicated small low-field J(sub c) enhancements at 77K in YBCO+Y211 films but more than an order of magnitude improvement in high-field J(sub c) in YBCO+BSO films due to the differences in the microstructures.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 15, 2009
- Accession Number
- ADA561588
Entities
People
- Chakrapani V. Varanasi
- Hao Wang
- Jeong Hyo Lee
- John H. Burke
- L. Brunke
- Paul N. Barnes
Organizations
- Air Force Research Laboratory