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Measuring the quantum states of a mesoscopic SQUID using a small Josephson junction

René Lindell·Jari Penttilä·Mika Sillanpää·Pertti Hakonen
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Abstract

We have experimentally studied the energy levels of a mesoscopic SQUID using inelastic Cooper-pair tunneling. The tunneling in a small Josephson junction depends strongly on its electromagnetic environment. We use this fact to do energy level spectroscopy of a SQUID-loop by coupling it to a small junction. Our samples with strong quasiparticle dissipation are well described by a model of a particle localized in one of the dips in a cosine-potential, while in the samples with weak dissipation we can see formation of energy bands.

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René Lindell, Jari Penttilä, Mika Sillanpää, Pertti Hakonen. 2003-03-25. Measuring the quantum states of a mesoscopic SQUID using a small Josephson junction. https://doi.org/10.1103/physrevb.68.052506

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