COHERENT CONTROL OF THE POLARIZATION OF AN OPTICAL-FIELD

Through use of quantum coherence in an atomic system, we demonstrate t hat an optical field can be used to completely control the polarizatio n state of another field. Theoretical and experimental results show th at by applying a field with a frequency tuned near one transition, an initially isotropic atomic vapor can be made to behave as a linearly o r circularly birefringent material for fields tuned near an adjoining transition. [S0031-9007(98)07434-1].