Enhancement of terahertz fields generation on a silver surface under the effect of short-wavelength femtosecond pulses

Abstract

The pulse shape of low-frequency surface and quasi-cylindrical waves arising under the effect of a femtosecond pulse of laser radiation focused into a strip on a silver surface is studied. In silver, the effective electron collisions frequencies in the laser pulse field and in the low-frequency field may differ greatly. It is shown that for a large difference in the collision frequencies, conditions are possible when the field of surface wave exceeds the field of quasi-cylindrical wave, and the generation of low-frequency fields is mainly due to the inhomogeneous heating of electrons in the skin layer.