Enhancement of electromagnetically-induced transparency in a Doppler broadened medium
Résumé
We show that electromagnetically-induced transparency in a room-temperature vapor of alkali-metal atoms can be enhanced via a specific shaping of the atomic velocity distribution. In such a medium, the interplay between doppler broadening and the existence of several excited levels may lead to a vanishing transparency, which cannot be predicted in a generic Lambda-type three-level model. Here, we identify the underlying effects resulting in this phenomenon and evidence some velocity classes turning transparency into absorption. By excluding these specific atoms from the interaction process, an enhancement of the transparency contrast by a factor 5 is thereby demonstrated, with potential applications for metrology and quantum information processing.
Domaines
Physique Quantique [quant-ph]
Origine : Fichiers produits par l'(les) auteur(s)