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

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 نشر من قبل Goran Karapetrov
 تاريخ النشر 2002
  مجال البحث فيزياء
والبحث باللغة English
 تأليف U. Welp




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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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