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arXiv · 0812.1865

Life after charge noise: recent results with transmon qubits

A. A. Houck·Jens Koch·M. H. Devoret·S. M. Girvin·R. J. Schoelkopf
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Abstract

We review the main theoretical and experimental results for the transmon, a superconducting charge qubit derived from the Cooper pair box. The increased ratio of the Josephson to charging energy results in an exponential suppression of the transmon's sensitivity to 1/f charge noise. This has been observed experimentally and yields homogeneous broadening, negligible pure dephasing, and long coherence times of up to 3 microseconds. Anharmonicity of the energy spectrum is required for qubit operation, and has been proven to be sufficient in transmon devices. Transmons have been implemented in a wide array of experiments, demonstrating consistent and reproducible results in very good agreement with theory.

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A. A. Houck, Jens Koch, M. H. Devoret, S. M. Girvin, R. J. Schoelkopf. 2008-12-10. Life after charge noise: recent results with transmon qubits. https://doi.org/10.1007/s11128-009-0100-6

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