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Updated: Aug 17, 2026

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Nonequilibrium quasiparticles and 2e periodicity in single-Cooper-pair transistors
J Aumentado1, Mark W Keller, John M Martinis
1National Institute of Standards and Technology, Boulder, Colorado 80305-3337, USA. jose.aumentado@boulder.nist.gov
Abstract:
We have fabricated single-Cooper-pair transistors in which the spatial profile of the superconducting gap energy was controlled by oxygen doping. The profile dramatically affects the switching current vs gate voltage curve of the transistor, changing its period from 1e to 2e. A model based on nonequilibrium quasiparticles in the leads explains our results, including the observation that even devices with a clean 2e period are "poisoned" by small numbers of these quasiparticles.
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