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A Mesoscopic Resonating Valence Bond system on a triple dot

Karyn Le Hur·Patrik Recher·Emilie Dupont·Daniel Loss
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Abstract

We introduce a mesoscopic pendulum from a triple dot. The pendulum is fastened through a singly-occupied dot (spin qubit). Two other strongly capacitively islands form a double-dot charge qubit with one electron in excess oscillating between the two low-energy charge states (1,0) and (0,1); this embodies the weight of the pendulum. The triple dot is placed between two superconducting leads as shown in Fig. 1. Under well-defined conditions, the main proximity effect stems from the injection of resonating singlet (valence) bonds on the triple dot. This gives rise to a Josephson current that is charge- and spin-dependent. Consequences in a SQUID-geometry are carefully investigated.

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Karyn Le Hur, Patrik Recher, Emilie Dupont, Daniel Loss. 2006-02-13. A Mesoscopic Resonating Valence Bond system on a triple dot. https://doi.org/10.1103/physrevlett.96.106803

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