Abstract
Simultaneous laser pulse compression and frequency down conversion in nonlinear crystals is a topic that draws a particular attention nowadays. Laser sources with a femtosecond pulse width are important for a variety of applications in the fields of material processing, biotechnology, medicine, environmental monitoring, and ultra-fast chemistry. These techniques make a superior progress and a significant influence to a mass of researches. Methods of ultra-short pulses generation through optical parametric generation and optical parametric amplification of a laser beat wave are described. Numerical simulation shows as much as 90 folds pulse compression in the generated signal laser pulse with a peak power exceeding the pump one. The group velocity mismatch effect and the exponential gain for the OPG process contributed to the pulse compression. The pulse width will be further compressing due to the phase locked side band generation in the beat wave OPA process. Not only the simulation result is showed, but the clear physical concepts are also described in this dissertation. I hope sincerely this thesis will be contributive to the research in this field, and the expansions of my thesis will be conductive to the human life.