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arXiv · 0911.2107

Enhanced superconductivity of YBCO interfaces: origin of high critical temperature in layered superconductors

S. S. Tinchev
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Abstract

Superconducting transition temperatures Tc of the YBCO film surface and of the YBCO film/substrate interface were measured inductively. It was observed that the interface- Tc is always higher then the surface - Tc. However deposition of silver over-layer enhances the superconducting transition temperatures. This observation was confirmed by four-point resistance measurements. In the annealed YBCO/Ag bilayers magnetic properties of the interface were observed. We believe that such phenomena are a common feature of layered systems. This two dimensional structure reminds the layered microstructure of the high-temperature superconductors and one can suppose that covering of the superconducting layer by non-superconducting layer is a condition for obtaining high critical temperatures in general.

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S. S. Tinchev. 2009-11-11. Enhanced superconductivity of YBCO interfaces: origin of high critical temperature in layered superconductors. https://doi.org/10.1016/j.physc.2010.06.003

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