Artificial nonlinear media with a resonant absorber

Md. Aminul Islam Talukder

Yu. N. Dubnishchev, T. Ya. Popova

Robert S. Afzal, W. P. Lin, N. M. Lawandy

Nonlinear beam propagation in absorbing media was originally examined by numerical simulations of the propagation of an electric field interacting with homogeneously broadened two-level atoms.1,2 Two significant predictions of the theory were cw on-resonance enhancement (CORE) and Fresnel ring encoding on the propagating beam. CORE has been observed in sodium vapor experiments3 where the center intensity of a beam traveling through an absorbing media increased by 69%. Fresnel ring encoding of an Ar-ion laser beam propagating through a sample of pink ruby has also been demonstrated.4 We further the work by discussing the experimental study of the effect of an absorbing birefringent media on a propagating laser beam.

Igor' M Bel'dyugin, А. А. Степанов, Vladimir A. Shcheglov

A system of equations is derived to describe a transient opposed degenerate four-wave interaction (FWI) in fields of arbitrary intensity in gaseous media exhibiting resonant and thermal nonlinearity mechanisms. A system of closed equations describing an opposed degenerate FWI in fields of arbitrary intensity is obtained for the steady-state case. It is found that, unlike linearly absorbing media, the optimal reflection coefficients of a signal wave in nonlinearly absorbing media are only achieved at reference wave intensities comparable with the saturation intensity of the resonant medium. Numerical calculations illustrate a fall in the reflection coefficient as the amplitude of the signal wave is increased.

Chonggang Wu, X. Li, Z. Wang

Alexander A. Zabolotskii

Perturbation theory is used in a study of the dynamics of an optical soliton in a ring resonator with a nonlinearly absorbing cell and external pumping. It is shown that the influence of impurity atoms with a saturable transition may give rise to a hysteretic dependence of the soliton amplitude at the exit from the resonator on the amplitude of a monochromatic pump field.