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arXiv · 0707.0732

Parity effect in Al and Nb single electron transistors in a tunable environment

A. M. Savin·M. Meschke·J. P. Pekola·Yu. A. Pashkin·T. F. Li·H. Im·J. S. Tsai
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Abstract

Two different types of Cooper pair transistors, with Al and Nb islands, have been investigated in a tunable electromagnetic environment. The device with an Al island demonstrates gate charge modulation with 2e-periodicity in a wide range of environmental impedances at bath temperatures below 340 mK. Contrary to the results of the Al sample, we were not able to detect 2e-periodicity under any conditions on similar samples with Nb island. We attribute this to the material properties of Nb.

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A. M. Savin, M. Meschke, J. P. Pekola, Yu. A. Pashkin, T. F. Li, H. Im, J. S. Tsai. 2007-07-05. Parity effect in Al and Nb single electron transistors in a tunable environment. https://doi.org/10.1063/1.2768897

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