High-order harmonic generation of picosecond radiation of moderate intensity in laser plasma

Abstract

The results of investigations into the generation of highorder harmonics (up to the 21st order) of picosecond (τ = 38 ps) Nd : YAG laser radiation in the plasma produced by laser ablation of metal and carbon-containing material surfaces are presented. We demonstrate the feasibility of generating high-order harmonics in the vacuum ultraviolet spectral range (with radiation wavelengths shorter than 120 nm) in plasmas with an efficiency of ∼0.7 × 10-4. In carbon-containing plasma, the 7th harmonic intensity exceeded that of the 5th one by a factor of seven.