Coherent amplification of the short optical pulse in a non-linear birefringent medium

The propagation of the solitary waves in the resonant birefringent amplifier with linear losses is considered. The birefringent optical linear medium contains two-level atoms with the upper state degenerated over projection of angular moment. It is assumed that population of resonance levels of atoms is inverted. The steady state pulse of polarized radiation that is vectonal generalization of the known π-pulse was analytically found. Numerical simulations demonstrate the formation dynamics solitary waves originated in birefringent amplifier.