Abstract

In the case of the scattering Raman amplification of light beams in a field of powerful ultrashort pulses, the back influence of the amplified radiation on the fundamental wave may be significant. Moreover, properties of the media, such as a population of atomic states, may significantly change. That leads to amplitude-phase modulation of the fundamental pulse owing to change of direction of intensity exchange in the pulse.¹ As a result, the bond between the fundamental and Stokes waves becomes weaker, that results in a decrease in the frequency conversion efficiency. For spatial inhomogeneous beams this effect is different in various beam sections.

© 1994 IEEE