Experimental study of harmonic generation from solid surfaces irradiated by multipicosecond laser pulses.

An experimental study is presented on harmonic generation from solid surfaces using 27 ps Nd:glass laser pulses (l51053 nm) in the intensity range of 10–10 W cm. Second, third, and fourth harmonics emitted in the specular reflection direction showed intensity scaling exponents of 1.5, 1.8, and 3.8 for an obliquely incident p-polarized laser beam, providing a conversion efficiency of 2310, 10, and 5 310 at 10 W cm, respectively. Second and third harmonic radiation generated using an s-polarized pump was about 10 and 100 times smaller, respectively, compared to that for the p-polarized laser radiation. Faraday rotation observed in the reflected fundamental radiation can explain the relative harmonic yields for the p and s polarizations of the pump beam.