Commensurate vortex pinning in Nb films patterned onto anodized aluminum oxide
نویسندگان
چکیده
Anodic aluminum oxide templates containing extended arrays of holes with 30-nm diameter and approximately 128-nm spacing were sputter-coated with Nb. We find pronounced matching effects in the transport and magnetization measurements beyond 4 kOe. In addition, we observe Little–Parks oscillations of the superconducting critical temperature. We compare the flux pinning in the patterned samples to unpatterned reference samples and find a significant enhancement of the critical current. Published by Elsevier B.V. PACS: 74.60.Ge; 74.76.Db
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Commensurability and strong vortex pinning in nanopatterned Nb films
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