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Unitary time-dependent superconvergent technique for pulse-driven quantum dynamics

D. Daems·A. Keller·S. Guérin·H. -R. Jauslin·O. Atabek
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Abstract

We present a superconvergent Kolmogorov-Arnold-Moser type of perturbation theory for time-dependent Hamiltonians. It is strictly unitary upon truncation at an arbitrary order and not restricted to periodic or quasiperiodic Hamiltonians. Moreover, for pulse-driven systems we construct explicitly the KAM transformations involved in the iterative procedure. The technique is illustrated on a two-level model perturbed by a pulsed interaction for which we obtain convergence all the way from the sudden regime to the opposite adiabatic regime.

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D. Daems, A. Keller, S. Guérin, H. -R. Jauslin, O. Atabek. 2003-01-17. Unitary time-dependent superconvergent technique for pulse-driven quantum dynamics. https://doi.org/10.1103/physreva.67.052505

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