Soliton propagation in a medium with Kerr nonlinearity and resonant impurities: a variational approach.

Using a variational approach we have studied the shape preserving coherent propagation of light pulses in a resonant dispersive medium in the presence of the Kerr nonlinearity. Within the framework of a combined nonintegrable system composed of one nonlinear Schrödinger and a pair of Bloch equations, we show the existence of a solitary wave. We have tested our analytical solution through numerical simulations confirming its solitary wave nature.

Coherent interaction effects in pulses propagating through a doped nonlinear dispersive medium.

Using a numerical approach we report on the cloning dynamics of simultaneous self-induced transparency (SIT) and nonlinear Schrödinger (NLS) solitons in a doped nonlinear dispersive medium. This technique involves a three-level atomic system interacting resonantly with two optical fields within a Lambda scheme. As a result, a pulse in the signal frequency is transformed into a replica of the pulse in the pump frequency. The atomic population evolution shows that the basic mechanism behind the cloning process is the coherent population trapping effect. Furthermore, it is shown that the signal clone presents characteristics of both the SIT soliton and NLS soliton.

Observation of image transfer and phase conjugation in stimulated down-conversion.

We observe experimentally the transfer of angular spectrum and image formation in the process of stimulated parametric down-conversion. Images and interference patterns can be transferred from either the pump or the auxiliary laser beams to the stimulated down-converted one. The stimulated field propagates as the complex conjugate of the auxiliary laser. The phase conjugation is observed through intensity pattern measurements.