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arXiv · 1003.5430

Superconducting transition in Nb nanowires fabricated using focused ion beam

G. C. Tettamanzi·C. I. Pakes·A. Potenza·S. Rubanov·C. H. Marrows·S. Prawer
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Abstract

Making use of focused Ga-ion beam (FIB) fabrication technology, the evolution with device dimension of the low-temperature electrical properties of Nb nanowires has been examined in a regime where crossover from Josephson-like to insulating behaviour is evident. Resistance-temperature data for devices with a physical width of order 100 nm demonstrate suppression of superconductivity, leading to dissipative behaviour that is shown to be consistent with the activation of phase-slip below Tc. This study suggests that by exploiting the Ga-impurity poisoning introduced by the FIB into the periphery of the nanowire, a central superconducting phase-slip nanowire with sub-10 nm dimensions may be engineered within the core of the nanowire.

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G. C. Tettamanzi, C. I. Pakes, A. Potenza, S. Rubanov, C. H. Marrows, S. Prawer. 2010-03-29. Superconducting transition in Nb nanowires fabricated using focused ion beam. https://doi.org/10.1088/0957-4484%2F20%2F46%2F465302

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