| Pulsed Laser Deposition of YBCO With Yttrium Oxide Buffer Layers (Postprint) |
Feb 2012 |
12 pages |
| Authors:
Paul N Barnes; Timothy J Haugan; Nick A Yust; Juliana M Evans; Justin C Tolliver; Rama M Nekkanti; Lyle B Brunke; Iman Maartense; John P Murphy; Srinivas Sathiraju; UES INC DAYTON OH
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 | Textured metallic substrate based HTS coated conductors with the YBCO/CeO2/YSZ/CeO2/Ni architecture have already been shown to exhibit high current densities. The CeO2 seed layer can effectively minimize the formation of NiO during the initial deposition on Ni and the CeO2 cap layer provides good lattice matching to the subsequent YBCO layer. However, there are reports of cracks developing in the CeO2 seed layer after a thicker growth due to a ... |
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| Correlation of AC Loss Data from Magnetic Susceptibility Measurements with YBCO Film Quality (Postprint) |
Feb 2012 |
5 pages |
| Authors:
Paul N Barnes; Timothy J Haugan; Amanda L Westerfield; Lyle B Brunke; Srinivas Sathiraju; Justin C Tolliver; Iman Maartense; Timothy L Peterson; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
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| It has been previously suggested that with spreading of the temperature-dependent ac susceptibility curves with increasing applied magnetic field, the quality of the YBCO film generally decreases. However, a documented study of this correlation to current transport properties using the imaginary or loss component of ac susceptibility data is not available. A detailed study was performed using the available data on YBCO films produced by pulsed laser deposition on different ... |
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| Pr Doped YBCO Films Produced by Pulsed Laser Deposition (Postprint) |
Feb 2012 |
8 pages |
| Authors:
B C Harrison; Joseph W Kell; Paul N Barnes; Timothy J Haugan; Chakrapani V Varanasi; Iman Maartense; Manisha V Rane; Frank Ramos; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIR/POWER DIV/MECHANICAL ENERGY CONVERSION BRANCH
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| Pr doped YBa2Cu3O7-d targets with composition Y1-xPrxBa2Cu3O7-d where x = 0.0001, 0.001, 0.01, and 0.1 were prepared from oxide powders and used to deposit thin films by pulsed laser deposition using conditions previously optimized for pure YBa2Cu3O7-d. The Pr dopant was found to be dispersed throughout the film by secondary ion mass spectrometry and the doped films had an increased density of nanoparticles on the surface. The pinning force of ... |
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| Textured Ion-Beam Assisted Deposition: Magnesium Oxide Template on Non-Metallic Flexible Ceraflex for Epitaxial Growth of Perovskite Films (Postprint) |
Aug 2007 |
10 pages |
| Authors:
Rongtao Lu; Judy Z Wu; Chakrapani Varanasi; Iman Maartense; Paul N Barnes; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIR/POWER DIV/MECHANICAL ENERGY CONVERSION BRANCH
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| This paper reports on a systematic study of the development of bi-axially textured magnesium oxide (MgO) templates on flexible ceramic polycrystalline ceraflex substrates by ion-beam assisted deposition (IBAD) and the preliminary test of the growth of YBa2Cu3O7 on top. The rough surface of the original ceraflex, with a typical roughness of about 100 nm, presented a serious challenge in the development of textured IBAD-MgO. By a coating of multiple layers ... |
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| Flux Pinning of Y-Ba-Cu-O Films Doped With BaZrO3 Nanoparticles by Multilayer and Single Target Methods (Postprint) |
Jun 2007 |
7 pages |
| Authors:
Timothy J Haugan; Paul N Barnes; Timothy A Campbell; Neal A Pierce; F J Baca; Iman Maartense; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIR/POWER DIV/MECHANICAL ENERGY CONVERSION BRANCH
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| The superconducting properties of YBa2Cu3O7-x (YBCO or 123) thin films doped with BaZrO3 (BZO) nanoparticles by multilayer and single-target methods were studied and compared. Thin films of 123 + BZO were processed by pulsed laser deposition on LaAlO3 and SrTiO3 single crystal substrates. Multilayer (BZO 0.6 nm - 1.4 nm /23(sub 15) nm)19 structures were grown by alternating deposition from 123 and BZO targets, and BZO additions of 0-2 Vol% ... |
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| Addition of Alternate Phase Nanoparticle Dispersions to Enhance Flux Pinning of Y-Ba-Cu-O Thin Films |
OCT 2004 |
6 pages |
| Authors:
Timothy J. Haugan; Paul N. Barnes; Timothy A. Campbell; Julianna M. Evans; Joseph W. Kell; Lyle B. Brunke; John P. Murphy; Chakrapani Varanasi; Iman Maartense; Winnie Wong-Ng; Lawrence P. Cook; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
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| Nanoparticle dispersions of various phases were added to YBa2Cu3O7(7-x) (YBCO or 123) thin films by multilayer pulsed laser deposition, to determine their effect on flux pinning. The different pinning materials examined include Y2BaCuO5 (Y211 or green-phase), La2BaCuO5 (La211 or brown-phase), Y2O3, CeO2, and MgO, with lattice constant mismatches varying from 0.5% to 12% with respect to YBCO. Y211 and Y2O3 provided significant pinning increases at temperatures of 65 K and ... |
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| Correlation Between the XPS Peak Shapes of Y(1)Ba(2)Cu(3)O(7-x )and Film Quality (Postprint) |
JUN 2003 |
6 pages |
| Authors:
Paul N. Barnes; Sharmila M. Mukhopadhyay; Timothy J. Haugan; Swaminathan Krishnaswami; Justin C. Tolliver; Iman Maartense; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
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| X-ray photoelectron spectroscopy (XPS) depth profiling was used to investigate the compositional and chemical profile of a typical YBCO coated conductor architecture. Results of the process revealed that the Y(3d) photoelectronic peak shape in these films is very different from bulk YBCO. To investigate this, several samples of Y1Ba2Cu3O7-x thin films were intentionally created of varying quality. The films were deposited on LaAlO3 by pulsed laser deposition with Jc values ... |
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