arXiv:1205.0217 · Physical Review A

Automated synthesis of dynamically corrected quantum gates

Kaveh Khodjasteh, Hendrik Bluhm, Lorenza Viola

Published Oct 22, 2012• 59 citations

Abstract

Dynamically corrected gates are extended to non-Markovian open quantum systems where limitations on the available controls and/or the presence of control noise make existing analytical approaches unfeasible. A computational framework for the synthesis of dynamically corrected gates is formalized that allows sensitivity against non-Markovian decoherence and control errors to be perturbatively minimized via numerical search, resulting in robust gate implementations. Explicit sequences for achieving universal high-fidelity control in a singlet-triplet spin qubit subject to realistic system and control constraint are provided, which simultaneously cancel to the leading order the dephasing due to non-Markovian nuclear-bath dynamics and voltage noise affecting the control fields. Substantially improved gate fidelities are predicted for current laboratory devices.

DOI: 10.1103/physreva.86.042329

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