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arXiv · 0802.0903

High-fidelity gates in a Josephson qubit

Erik Lucero·M. Hofheinz·M. Ansmann·Radoslaw C. Bialczak·N. Katz·Matthew Neeley·A. D. O'Connell·H. Wang·A. N. Cleland·John M. Martinis
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Abstract

We demonstrate new experimental procedures for measuring small errors in a superconducting quantum bit (qubit). By carefully separating out gate and measurement errors, we construct a complete error budget and demonstrate single qubit gate fidelities of 0.98, limited by energy relaxation. We also introduce a new metrology tool -- a Ramsey interference error filter -- that can measure the occupation probability of the state $\ket{2}$ down to $10^{-4}$, a magnitude near the fault tolerant threshold.

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Erik Lucero, M. Hofheinz, M. Ansmann, Radoslaw C. Bialczak, N. Katz, Matthew Neeley, A. D. O'Connell, H. Wang, A. N. Cleland, John M. Martinis. 2008-02-07. High-fidelity gates in a Josephson qubit. https://doi.org/10.1103/physrevlett.100.247001

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