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Entanglement and teleportation of macroscopic continuous variables by superconducting devices

L. Fisch·I. E. Mazets·G. Kurizki
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Abstract

A current-biased low-temperature superconducting Josephson junction (JJ) is dynamically describable by the quantized motion of a fictitious particle in a "washboard" potential. The long coherence time of tightly-bound states in the washboard potential of a JJ has prompted the effort to couple JJs and operate them as entangled qubits, capable of forming building blocks of a scalable quantum computer. Here we consider a hitherto unexplored quantum aspect of coupled JJs: the ability to produce Einstein-Podolsky-Rosen (EPR) entanglement of their continuous variables, namely, their magnetic fluxes and induced charges. Such entanglement, apart from its conceptual novelty, is the prerequisite for a far-reaching goal: teleportation of the flux and charge variables between JJs, implementing the transfer of an unknown quantum state along a network of such devices.

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L. Fisch, I. E. Mazets, G. Kurizki. 2005-04-20. Entanglement and teleportation of macroscopic continuous variables by superconducting devices. https://arxiv.org/abs/quant-ph/0504153

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