Publisher’s Note: Optimized time-dependent perturbation theory for pulse-driven quantum dynamics in atomic or molecular systems [Phys. Rev. A68, 051402 (2003)]

Time-dependent unitary perturbation theory for intense laser-driven molecular orientation

“…This section recalls the principles of TDUPT as constructed in [22,23]. The presentation followed here highlights the analogy of this procedure with the spirit of the interaction picture.…”

“…In other respects, it has recently been shown that time-dependent problems generated by short pulses can be treated by a time-dependent unitary perturbation theory (TDUPT) [22,23,24], which is the time-dependent version of the perturbation theory using averaging techniques [25,26,27,28,29,30,31]. Analogous in its spirit to the interaction picture, this theory consists of a series of unitary transformations, which are aimed at rewriting the evolution operator as a product of other propagators.…”

“…Moreover, order by order (Van Vleck) and superexponential (Kolmogorov-Arnold-Moser) algorithms can be derived. A detailed calculation scheme is provided in recent papers [22,23] and its efficiency has been shown for a two-level Hamiltonian.…”

Pulse-driven quantum dynamics beyond the impulsive regime

“…In Ref. [15], we presented an improvment of this technique taking advantage of free parameters, connected to secular terms, that are available to reduce the error without prior knowledge of the exact solution. This optimization enhances the accuracy of the method in such a way that the first order approximation gives a satisfactory description up to fairly large values of the perturbative parameter.…”

“…The present article contains a detailed description of the methods announced in [15]. Instead of using an extended space, we formulate the derivation in a simpler way, by stating the perturbation iterations directly at the level of the evolution operator in the original Hilbert space.…”