2009/10/19 by Gandman, Andrey, Rybak, Leonid, Bronstein, Michal +2
#Atomic Physics (physics.atom-ph) #Chemical Physics (physics.chem-ph) #FOS: Physical sciences
paper · doi:10.48550/arxiv.0910.3581
We present and implement a new scheme for independent control of both the final and the transient population utilizing the symmetry properties of the system. By proper pulse shaping, utilizing the invariance of the two-photon absorption to specific phase transformations of the pulse, different time evolutions of the transient population are photo-induced for a given (fixed) final state population. The model system is the Na atom. The work is conducted in the weak-field regime for which the transient two-photon excitation is described by second-order perturbation theory. One most attractive case is the extended family of third-order chirp pulses which control the population build-up duration independently of the final population.