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arXiv · 1603.03082

Scalable in-situ qubit calibration during repetitive error detection

J. Kelly·R. Barends·A. G. Fowler·A. Megrant·E. Jeffrey·T. C. White·D. Sank·J. Y. Mutus·B. Campbell·Yu Chen·Z. Chen·B. Chiaro·A. Dunsworth·E. Lucero·M. Neeley·C. Neill·P. J. J. O'Malley·C. Quintana·P. Roushan·A. Vainsencher·J. Wenner·John M. Martinis
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Abstract

We present a method to optimize qubit control parameters during error detection which is compatible with large-scale qubit arrays. We demonstrate our method to optimize single or two-qubit gates in parallel on a nine-qubit system. Additionally, we show how parameter drift can be compensated for during computation by inserting a frequency drift and using our method to remove it. We remove both drift on a single qubit and independent drifts on all qubits simultaneously. We believe this method will be useful in keeping error rates low on all physical qubits throughout the course of a computation. Our method is O(1) scalable to systems of arbitrary size, providing a path towards controlling the large numbers of qubits needed for a fault-tolerant quantum computer

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J. Kelly, R. Barends, A. G. Fowler, A. Megrant, E. Jeffrey, T. C. White, D. Sank, J. Y. Mutus, B. Campbell, Yu Chen, Z. Chen, B. Chiaro, A. Dunsworth, E. Lucero, M. Neeley, C. Neill, P. J. J. O'Malley, C. Quintana, P. Roushan, A. Vainsencher, J. Wenner, John M. Martinis. 2016-03-09. Scalable in-situ qubit calibration during repetitive error detection. https://doi.org/10.1103/physreva.94.032321

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