Laser systems for the generation of picosecond high-irradiance light pulses

A laser system emitting 60–80 J pulses of (2–5) · 10^–11 sec duration was developed. Determinations were made of the energy densities corresponding to the threshold of the surface and internal damage of active elements by pulses of various durations. A multipass amplifier characterized by a gain up to 10³ was constructed. This made it possible to use a low-power master oscillator and to amplify its output. In this way, 0.6 J pulses of (5–10) · 10^–12 sec duration were generated. The directionality of these pulses was close to the diffraction limit. Further amplification of the light pulses made it possible to increase the output energy to 40 J, which corresponded to an irradiance of (4–5) · 10¹⁹ W · sr^–1 · cm^–2 in the diffraction angle and to an irradiance of over 10²⁰ W · sr^–1 · cm^–2 along the axis.