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arXiv · 1502.07739

Quantum optimal control within the rotating wave approximation

Maximilian Keck·Matthias M. Müller·Tommaso Calarco·Simone Montangero
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Abstract

We study the interplay between rotating wave approximation and optimal control. In particular, we show that for a wide class of optimal control problems one can choose the control field such that the Hamiltonian becomes time-independent under the rotating wave approximation. Thus, we show how to recast the functional minimization defined by the optimal control problem into a simpler multi-variable function minimization. We provide the analytic solution to the state-to-state transfer of the paradigmatic two-level system and to the more general star configuration of an $N$-level system. We demonstrate numerically the usefulness of this approach in the more general class of connected acyclic $N$-level systems with random spectra. Finally, we use it to design a protocol to entangle Rydberg via constant laser pulses atoms in an experimentally relevant range of parameters.

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Maximilian Keck, Matthias M. Müller, Tommaso Calarco, Simone Montangero. 2015-03-06. Quantum optimal control within the rotating wave approximation. https://doi.org/10.1103/physreva.92.033402

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