Abstract

The results of experimental investigations of parametric light amplifier (FLA), consisting of successively placed DCDA crystals, in frequency degenerate and nondegenerate regimes with a Nd³⁺:YAG laser second-harmonic nanosecond pulse pump, are discussed. The nonlinear crystals were oriented so that the relative phase mismatch signs in the neighboring crystals were opposite, but the nonlinear coefficient signs were the same, thus permitting a reduction of the sensitivity to radiation divergency.¹ In the experiments we had PLA, consisting of 1-4 DCDA crystals each 60-mm long with 63-mm air spacing between them. Second harmonic (SH) pump radiation was generated from the laser system² in DCDA crystal 90° phase- matching. The SH intensity was ≡100 MW/cm², with pulse duration τ ≡ 25 ns and beam diameter 10 mm.

© 1993 Optical Society of America