AMPLIFICATION AND SHAPING OF SHORT OPTICAL PULSES IN MULTILEVEL RESONANT MEDIUM

The propagation of ultrashort pulses in a multilevel amplifying medium is analyzed. It is shown that the resonant dispersion (wave packet dy namics) leads to inversionless generation of a series of pulses follow ing the main pulse. In case of a Raman scheme the anti-Stokes signal i s amplified with the same shape as the pump shape. The efficiency of c onversion can be significantly increased by applying a synchronous pum p, which eliminates the spread of the secondary pulses.