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arXiv · 1408.5679

Superconducting properties in tantalum decorated three-dimensional graphene and carbon structures

Cayetano S. F. Cobaleda·Xiaoyin Xiao·D. Bruce Burckel·Ronen Polsky·Duanni Huang·Enrique Diez·W. Pan
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Abstract

We present here the results on superconducting properties in tantalum thin films (100nm thick) deposited on three-dimensional graphene (3DG) and carbon structures. A superconducting transition is observed in both composite thin films with a superconducting transition temperature of 1.2K and 1.0K, respectively. We have further measured the magnetoresistance at various temperatures and differential resistance dV/dI at different magnetic fields in these two composite thin films. In both samples, a much large critical magnetic field (~ 2 Tesla) is observed and this critical magnetic field shows linear temperature dependence. Finally, an anomalously large cooling effect was observed in the differential resistance measurements in our 3DG-tantalum device when the sample turns superconducting. Our results may have important implications in flexible superconducting electronic device applications.

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Cayetano S. F. Cobaleda, Xiaoyin Xiao, D. Bruce Burckel, Ronen Polsky, Duanni Huang, Enrique Diez, W. Pan. 2014-08-25. Superconducting properties in tantalum decorated three-dimensional graphene and carbon structures. https://doi.org/10.1063/1.4892574

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