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

Daems, D.; Keller, A.; Guérin, S.; Jauslin, H. -R.; Atabek, O.

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

Authors

Description

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.
10 pages, 3 figures