title: Coherent excitation of a two-state system by a linearly chirped Gaussian pulse.
abstract: This work presents an analytic description of coherent excitation of a two-state quantum system by an external field with a Gaussian temporal shape and a linear frequency sweep. A very accurate analytic approximation to the transition probability in terms of the Lambert function is derived by using the Dykhne-Davis-Pechukas approach. This approximation provides analytic expressions for the frequency and the amplitude of the probability oscillations and for the ranges of interaction parameters where high transition probability is obtained.
authors.affiliation: Department of Physics, Sofia University, James Bourchier 5 Boulevard, 1164 Sofia, Bulgaria.
authors.forename: G S
authors.initials: GS
authors.lastname: Vasilev
authors.forename: N V
authors.initials: NV
authors.lastname: Vitanov