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arXiv · 1910.01090

Right-sizing fluxonium against charge noise

Ari Mizel·Yariv Yanay
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Abstract

We analyze the charge-noise induced coherence time $T_2$ of the fluxonium qubit as a function of the number of array junctions in the device, $N$. The pure dephasing rate decreases with $N$, but we find that the relaxation rate increases, so $T_2$ achieves an optimum as a function of $N$. This optimum can be much smaller than the number typically chosen in experiments, yielding a route to improved fluxonium coherence and simplified device fabrication at the same time.

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Ari Mizel, Yariv Yanay. 2019-10-02. Right-sizing fluxonium against charge noise. https://doi.org/10.1103/physrevb.102.014512

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