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Topology Induced Macroscopic Quantum Coherence in Josephson Junction Networks

G. Giusiano·F. P. Mancini·P. Sodano·A. Trombettoni
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Abstract

We argue that Josephson junction networks may be engineered to allow for the emergence of new and robust quantum coherent states. We provide a rather intuitive argument showing how the change in topology may affect the quantum properties of a bosonic particle hopping on a network. As a paradigmatic example, we analyze in detail the quantum and thermodynamic properties of non-interacting bosons hopping on a comb graph. We show how to explicitly compute the inhomogeneities in the distribution of bosons along the comb's fingers, evidencing the effects of the topology induced spatial Bose-Einstein condensation characteristic of the system. We propose an experiment enabling to detect the spatial Bose-Einstein condensation for Josephson networks built on comb graphs.

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G. Giusiano, F. P. Mancini, P. Sodano, A. Trombettoni. 2004-01-22. Topology Induced Macroscopic Quantum Coherence in Josephson Junction Networks. https://doi.org/10.1142/s0217979204024318

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