Spatial and temporal characteristics of ultrashort laser pulses propagation in resonance media

Laser propagating through resonance media taking into account of spatial effect was discussed by simultaneously solving the Maxwell-Bloch equations with definite differential method. Results indicate that the propagation of a 2π pulse form would no longer be a soliton, its profile would expand, and the degree of distortion depends on the interaction intensity of laser and material: stronger interaction causes more distortion till the profile split. The interaction intensity was decided by such elements as the laser frequency, laser intensity, the dipole of material, detuning and the concentration of resonance particles．