The flux qubit revisited to enhance coherence and reproducibility

  title={The flux qubit revisited to enhance coherence and reproducibility},
  author={Fei Yan and Simon Gustavsson and A Kamal and Jeffrey Birenbaum and Adam P. Sears and David J. Hover and Theodore J. Gudmundsen and Danna Rosenberg and Gabriel O. Samach and Steven J. Weber and Jonilyn L. Yoder and T. P. Orlando and John Clarke and Andrew J. Kerman and William D. Oliver},
  journal={Nature Communications},
The scalable application of quantum information science will stand on reproducible and controllable high-coherence quantum bits (qubits). Here, we revisit the design and fabrication of the superconducting flux qubit, achieving a planar device with broad-frequency tunability, strong anharmonicity, high reproducibility and relaxation times in excess of 40 μs at its flux-insensitive point. Qubit relaxation times T1 across 22 qubits are consistently matched with a single model involving resonator… 
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