Research in this program consists of a theoretical and experimental investigation of self-focusing of ultrashort laser pulses in nonlinear dispersive media. The studies characterize the temporal, spatial, and spectral focusing of a femtosecond laser pulse when its peak power is above the critical power for self-focusing. Using wide band-gap solid- state materials and high-pressure gases as nonlinear media, a wide range of experimental conditions are expected to be explored. One outgrowth of the research should be the determination of the range of applicability of the three- dimensional nonlinear Schroedinger equation to the nonlinear propagation of ultrashort pulses.
