Theoretical and experimental investigations of the colliding-pulse operation of solid-state lazers

An analysis is made of the interaction of ultrashort pulses with a two-level saturable absorber under colliding-pulse conditions. Reduction in the duration of Gaussian pulses is studied in a wide range of ultrashort pulse and absorber parameters and a comparison is made with traditional methods when an absorber is in contact or is not in contact with a nontransmitting mirror. An analysis of the dynamics of the strongest pulse made allowing for the noise radiation on the basis of a fluctuation model demonstrates that, apart from other known advantages attained in dye lasers, the colliding-pulse operation of solid-state lasers can reduce the duration of the strongest ultrashort pulse in a train near the second thresholds. It is shown theoretically and experimentally that this advantage of the colliding-pulse operation becomes more pronounced on increase in the rate of relaxation of the absorber.