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arXiv · 1402.5174

Robustness of composite pulses to time-dependent control noise

Chingiz Kabytayev·Todd J. Green·Kaveh Khodjasteh·Michael J. Biercuk·Lorenza Viola·Kenneth R. Brown
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Abstract

We study the performance of composite pulses in the presence of time-varying control noise on a single qubit. These protocols, originally devised only to correct for static, systematic errors, are shown to be robust to time-dependent non-Markovian noise in the control field up to frequencies as high as ~10% of the Rabi frequency. Our study combines a generalized filter-function approach with asymptotic dc-limit calculations to give a simple analytic framework for error analysis applied to a number of composite-pulse sequences relevant to nuclear magnetic resonance as well as quantum information experiments. Results include examination of recently introduced concatenated composite pulses and dynamically corrected gates, demonstrating equivalent first-order suppression of time-dependent fluctuations in amplitude and/or detuning, as appropriate for the sequence in question. Our analytic results agree well with numerical simulations for realistic $1/f$ noise spectra with a roll-off to $1/f^2$, providing independent validation of our theoretical insights.

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Chingiz Kabytayev, Todd J. Green, Kaveh Khodjasteh, Michael J. Biercuk, Lorenza Viola, Kenneth R. Brown. 2014-07-14. Robustness of composite pulses to time-dependent control noise. https://doi.org/10.1103/physreva.90.012316

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