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

A theory of matter-wave interference is developed in which resonant, standi ng-wave optical fields interact with an ensemble of two-level atoms. If eff ects related to the recoil the atoms undergo on absorbing or emitting radia tion 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 rec oil frequency. In this regime, the atoms exhibit matter-wave interference t hat can be used as the basis of a matter-wave atom interferometer. Two spec ific atom-field geometries are considered, involving either one or two fiel d-interaction zones. For each geometry, the recoil-induced spatial modulati on of the total atomic density is calculated. In contrast to the normal Tal bot and Tadbot-Lau effects, the spatially modulated density is not a period ic function of time, owing to spontaneous emission; however, after a suffic iently long time, the contribution from spontaneous processes no longer pla ys a role and the periodicity is restored. With a suitable choice of observ ation time and field strengths, the spatially modulated atomic density serv es as an indirect probe of the distribution of spontaneously emitted radiat ion. [S1050-2947(99)07803-8].