Optics and Spectroscopy
Coherent amplification of waves in an antidirectional fiber coupler containing resonance admixture atoms
Elena V. Kazantseva, Andrei I. Maimistov
Abstract
Two tunnel-coupled waveguides, one exhibiting positive refraction, the other exhibiting negative refraction, are analyzed. It is proposed that the positively refracting waveguide contains resonant admixture atoms, while the negatively refracting one has linear losses. The nonlinear properties of the positively refracting waveguide are related to saturation of resonance absorption. It is demonstrated that attenuation of a backward wave propagating in the studied antidirectional coupler can be compensated under certain conditions.