Vibronic coupling induced by fast Rabi oscillations for kinetic energy control in free atom

Vibronic coupling effects usually manifest themselves in molecules and crystals rather than in unbound atoms. We theoretically demonstrate the existence of vibronic states in a moving two-level atom exposed to a strong electromagnetic (EM) wave. In this case, the Rabi oscillations of the electron density give rise to periodic displacements of the atomic nucleus with the Rabi frequency. The periodic displacements mix the Stark split electron levels and lead to the establishment of a channel for energy transfer in the atomic system. Such a channel paves the way for fast control of the kinetic energy of a free atom with the use of the parameters of an EM wave. Thus, the system kinetic energy can be decreased or increased if the detuning between the laser pulse frequency and the optical transition is positive or negative, respectively. For actual values of the detuning, the pulse duration should be an order of magnitude longer than the lifetime of the excited atomic level in order to complete the energy transfer process. (paper)