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arXiv · 1009.6028

Interference and Switching of Josephson current carried by nonlocal spin-entangled electrons in a SQUID-like system with quantum dots

Zhi Wang·Xiao Hu
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Abstract

Josephson current of spin-entangled electrons through the two branches of a SQUID-like structure with two quantum dots exhibits a magnetic-flux response different from the conventional Josephson current. Due to their interference, the period of maximum Josephson current changes from $h/2e$ to $h/e$, which can be used for detecting the Cooper-pair splitting efficiency. The nonlocal spin entanglement provides a quantum mechanical functionale for switching on and off this novel Josephson current, and explicitly a switch is formulated by including a pilot junction. It is shown that the device can be used to measure the magnitude of split-tunneling Josephson current.

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Zhi Wang, Xiao Hu. 2010-12-25. Interference and Switching of Josephson current carried by nonlocal spin-entangled electrons in a SQUID-like system with quantum dots. https://doi.org/10.1103/physrevlett.106.037002

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