Self-focusing of broadband laser pulses in dispersive media.

摘要

We have modeled the propagation in a nonlinear dispersive medium of high power laser beams having spectral bandwidth with randomly phased components. Such pulses exhibit temporal noise which generally increases the effect of self focusing compared to single frequency pulses with the same average intensity. However, it is found that dispersive effects are greatly enhanced by the spectral broadening from self-phase-modulation. The combination of self-phase-modulation and dispersion can actually raise the threshold for self-focusing with increasing pulse bandwidth, although not to the level found for a single frequency beam.