ABSTRACT
In this chapter, I show some peculiarities in characterization of
plasma harmonics. They are mainly centered in definition of new
features of this process. Among them, the following results will be
discussed:
(a) I show the results of theoretical and experimental studies of
HHG in the ensemble of silver atoms irradiated by intense
femtosecond pulses of Ti:sapphire laser. It is shown during these
studies that the photoemission spectra exhibit unusual behavior
when the laser field strength approaches near-atomic values.