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arXiv · 2212.06627

Soliton versus single photon quantum dynamics in arrays of superconducting qubits

Ben Blain·Giampiero Marchegiani·Juan Polo·Gianluigi Catelani·Luigi Amico
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Abstract

Superconducting circuits constitute a promising platform for future implementation of quantum processors and simulators. Arrays of capacitively coupled transmon qubits naturally implement the Bose-Hubbard model with attractive on-site interaction. The spectrum of such many-body systems is characterised by low-energy localised states defining the lattice analog of bright solitons. Here, we demonstrate that these bright solitons can be pinned in the system, and we find that a soliton moves while maintaining its shape. Its velocity obeys a scaling law in terms of the combined interaction and number of constituent bosons. In contrast, the source-to-drain transport of photons through the array occurs through extended states that have higher energy compared to the bright soliton. For weak coupling between the source/drain and the array, the populations of the source and drain oscillate in time, with the chain remaining nearly unpopulated at all times. Such a phenomenon is found to be parity dependent. Implications of our results for the actual experimental realisations are discussed.

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Ben Blain, Giampiero Marchegiani, Juan Polo, Gianluigi Catelani, Luigi Amico. 2022-12-13. Soliton versus single photon quantum dynamics in arrays of superconducting qubits. https://doi.org/10.1103/physrevresearch.5.033130

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