arXiv:1601.02469 · Physical Review Letters

Single Quantum Level Electron Turnstile

D. M. T. van Zanten, D. M. Basko, Ivan M. Khaymovich, Jukka P Pekola, H. Courtois, Clemens B. Winkelmann

Published Apr 20, 2016• 40 citations

Abstract

We report on the realization of a single-electron source, where current is transported through a single-level quantum dot (Q) tunnel coupled to two superconducting leads (S). When driven with an ac gate voltage, the experiment demonstrates electron turnstile operation. Compared to the more conventional superconductor-normal-metal-superconductor turnstile, our superconductor-quantum-dot-superconductor device presents a number of novel properties, including higher immunity to the unavoidable presence of nonequilibrium quasiparticles in superconducting leads. Moreover, we demonstrate its ability to deliver electrons with a very narrow energy distribution.

DOI: 10.1103/physrevlett.116.166801

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