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arXiv · 1912.01018

Efficient modeling of superconducting quantum circuits with tensor networks

Agustin Di Paolo·Thomas E. Baker·Alexandre Foley·David Sénéchal·Alexandre Blais
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Abstract

We introduce an efficient tensor network toolbox to compute the low-energy excitations of large-scale superconducting quantum circuits up to a desired accuracy. We benchmark this algorithm on the fluxonium qubit, a superconducting quantum circuit based on a Josephson junction array with over a hundred junctions. As an example of the possibilities offered by this numerical tool, we compute the pure-dephasing coherence time of the fluxonium qubit due to charge noise and coherent quantum phase slips, taking into account the array degrees of freedom corresponding to a Hilbert space as large as$~15^{180}$. Our algorithm is applicable to the wide variety of circuit-QED systems and may be a useful tool for scaling up superconducting-qubit technologies.

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Agustin Di Paolo, Thomas E. Baker, Alexandre Foley, David Sénéchal, Alexandre Blais. 2019-12-02. Efficient modeling of superconducting quantum circuits with tensor networks. https://doi.org/10.1038/s41534-020-00352-4

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