High-efficiency second-harmonic generation of superintense ultrashort laser pulses

摘要

The effect of instantaneous cubic nonlinearity on second-harmonic generation of femtosecond laser pulses is investigated. The possibility of improving generation efficiency and shortening pulse duration is analyzed. Energy conversion efficiency of 60percent was obtained in an experiment in a 1 mm thickness KDP crystal at the peak intensity of 0.6 TW/cm~(2) and the duration of 60 fs.