Theory of the quasi-steady-state self-focusing of partially coherent light pulses in nonlinear media.

The quasi-steady-state (QSS) self-focusing of partially coherent light pulses (PCLPs) in nonlinear media is studied. The analytical formulas of the QSS self-focusing of PCLPs in nonlinear media (e.g., the beam width, spatial coherence width, and focal length) are presented. The effect of spatial coherence on the focal length and focus moving is investigated in detail. In particular, it is found that a PCLP has more advantages to avoid the optical damage of materials than a fully coherent light pulse.