Matter-wave interference using two-level atoms and resonant optical fields

Abstract

A theory of matter-wave interference is developed in which resonant, standing-wave optical fields interact with an ensemble of two-level atoms. If effects related to the recoil the atoms undergo on absorbing or emitting radiation are neglected, the total atomic density is spatially uniform. However, when recoil effects are included, spatial modulation of the atomic density can occur for times that are greater than or comparable to the inverse recoil frequency. In this regime, the atoms exhibit matter-wave interference that can be used as the basis of a matter-wave atom interferometer. Two specific atom-field geometries are considered, involving either one or two field-interaction zones. For each geometry, the recoil-induced spatial modulation of the total atomic density is calculated. In contrast to the normal Talbot and Talbot-Lau effects, the spatially modulated density is nota periodic function of time, owing to spontaneous emission; however, after a sufficiently long time, the contribution from spontaneous processes no longer plays a role and the periodicity is restored. With a suitable choice of observation time and field strengths, the spatially modulated atomic density serves as an indirect probe of the distribution of spontaneously emitted radiation.