ANOMALOUS TRANSMISSION IN ATOM OPTICS

Anomalous transmission for X-rays in crystals as discovered by Borrman n can also be observed for atoms interacting with a standing light wav e on resonance. It may be interpreted as a manifestation of a grey sta te. We describe phenomena based on anomalous transmission for various regimes of the atom-light interaction and elucidate these by numerical calculations for argon and calcium. The grey state in anomalous trans mission is linked to the dark state in velocity selective coherent pop ulation trapping in atomic three-level Lambda systems.