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arXiv · 1810.11006

The high-coherence fluxonium qubit

Long B. Nguyen·Yen-Hsiang Lin·Aaron Somoroff·Raymond Mencia·Nicholas Grabon·Vladimir E. Manucharyan
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Abstract

We report superconducting fluxonium qubits with coherence times largely limited by energy relaxation and reproducibly satisfying T2 > 100 microseconds (T2 > 300 microseconds in one device). Moreover, given the state of the art values of the surface loss tangent and the 1/f flux noise amplitude, coherence can be further improved beyond 1 millisecond. Our results violate a common viewpoint that the number of Josephson junctions in a superconducting circuit -- over 100 here -- must be minimized for best qubit coherence. We outline how the unique to fluxonium combination of long coherence time and large anharmonicity can benefit both gate-based and adiabatic quantum computing.

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Long B. Nguyen, Yen-Hsiang Lin, Aaron Somoroff, Raymond Mencia, Nicholas Grabon, Vladimir E. Manucharyan. 2018-10-25. The high-coherence fluxonium qubit. https://doi.org/10.1103/physrevx.9.041041

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