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Superconducting Transition and Vortex Pinning in Nb Films Patterned with Nano-scale Hole-arrays

U. Welp·Z. L. Xiao·J. S. Jiang·V. K. Vlasko-Vlasov·S. D. Bader·G. W. Crabtree·J. Liang·H. Chik·J. M. Xu
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Abstract

Nb films containing extended arrays of holes with 45-nm diameter and 100-nm spacing have been fabricated using anodized aluminum oxide (AAO) as substrate. Pronounced matching effects in the magnetization and Little-Parks oscillations of the superconducting critical temperature have been observed in fields up to 9 kOe. Flux pinning in the patterned samples is enhanced by two orders of magnitude as compared to unpatterned reference samples in applied fields exceeding 5 kOe. Matching effects are a dominant contribution to vortex pinning at temperatures as low as 4.2 K due to the extremely small spacing of the holes.

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U. Welp, Z. L. Xiao, J. S. Jiang, V. K. Vlasko-Vlasov, S. D. Bader, G. W. Crabtree, J. Liang, H. Chik, J. M. Xu. 2002-04-24. Superconducting Transition and Vortex Pinning in Nb Films Patterned with Nano-scale Hole-arrays. https://doi.org/10.1103/physrevb.66.212507

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