title: Coherent control of the effective susceptibility through wave mixing in a duplicated two-level system.
abstract: We theoretically demonstrate the coherent control of the effective susceptibility of a duplicated two-level system. The control is obtained for a linearly polarized weak field in the presence of a much stronger orthogonally polarized field. For small optical depths, the effective susceptibility chi(eff) behaves as chilin(e 2iphi) (chilin) is the linear susceptibility, phi the phase shift) allowing coherent control of the optical response. For large optical depths, chi(eff) approximately chi(lin), turning an absorber into an amplifier without affecting the dispersion.
authors.affiliation: Laboratoire de Collisions Agrégats Réactivité, C.N.R.S. UMR 5589, IRSAMC Université Paul Sabatier, 31062 Toulouse Cedex 4, France.
authors.forename: F A
authors.initials: FA
authors.lastname: Hashmi
authors.forename: M A
authors.initials: MA
authors.lastname: Bouchene