Местоположение издательства:New York [etc.], United States
Первая страница:241
Последняя страница:252
Аннотация:It was found that modification of the physicalproperties of the surface layer of a target makes it possible to control, effectively and within a wide range, the characteristics of a femtosecond laser plasma (temperature, degree of ionisation, emissivity, and nonlinear-optical susceptibil-ity) at moderate intensities of 10^15^10^16 W/cm2, which are optimal for promising laser-plasma femtosecond technologies. The targets used in an experimental investigation ultrafine freely suspended films and porous materials. Potential applications of such targets at intensities above 10^17 W/cm2 were considered.Intense interfering beams generated a high-temperature near-surface femtosecond plasma with periodically modulated parameters. The dynamics of the efficiency of diffraction by such an induced 'grating' was studied. A background-free method for measuring the duration of high-intensity laser pulses on the basis of noncollinear second-harmonic generation was demonstrated. An increase in the second-harmonic signal was observed for the first time under the conditions of resonant excitation of a surface electromagnetic wave by high-intensity radiation of femtosecond duration.