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Enhanced flux pinning in YBa2Cu3O7-d films by nano-scaled substrate surface roughness

Zuxin Ye·W. D. Si·Qiang Li·Y. Hu·P. D. Johnson·Y. Zhu
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Abstract

Nano-scaled substrate surface roughness is shown to strongly influence the critical current density Jc in YBCO films made by pulse-laser-deposition on the crystalline LaAlO3 substrates consisting of two separate twin-free and twin-rich regions. The nano-scaled corrugated surface was created in the twin-rich region during the deposition process. Using magneto-optical imaging techniques coupled with optical and atomic force microscopy, we observed an enhanced flux pinning in the YBCO films in the twin-rich region, resulted in \~30% increase in Jc, which was unambiguously confirmed by the direct transport measurement.

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Zuxin Ye, W. D. Si, Qiang Li, Y. Hu, P. D. Johnson, Y. Zhu. 2005-08-22. Enhanced flux pinning in YBa2Cu3O7-d films by nano-scaled substrate surface roughness. https://doi.org/10.1063/1.2051794

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