Studying the Parameters of Second Harmonic Generation under the Conditions of a Weakly Chirped Pulse

详细

Results are presented from studying the parameters of second harmonic radiation under conditions of the transformation of a positively and negatively chirped pulse of fundamental frequency. It is shown that when the duration of a bandwidth-limited pulse (50 fs) is increased to 630 fs and beyond, the distribution of second harmonic intensity becomes close to Gaussian. The efficiency of second harmonic generation with duration of 2.5 ps falls from 38.69 to 4%, and the quality of the second harmonic improves until it becomes equal to М² = 1.3. Substantial modulation of the amplitude and the narrowing of the second harmonic spectrum are observed upon negative chirping of the fundamental frequency.