STUDY OF NEON-LIKE LASING IN GALLIUM

We report the observation of lasing in neon-like gallium on the J = 0- 1, 2-1, and 1-1 transitions at 20.4, 24.7, 25.1, and 26.2 nm. The expe riment was carried out on the Asterix IV iodine laser with and without a prepulse. It was found that without a prepulse, only weak lasing wa s observed on the J = 2-1 transitions at 24.7 and 25.1 mm, and the J = 0-1 transition at 20.4 nn, lased only marginally. The application of a prepulse 5.23 ns before the main pulse enhanced the J = 0-1 laser ou tput at 20.4 nm by two orders of magnitude. The pair of J = 21 Lasers were also enhanced, The gain coefficients were measured to be 4.3, 3.1 , and 2.8 cm(-1) for the 20.4-, 24.7-, and 25.1-nm lasers, respectivel y. A comparison with germanium and zinc when no prepulse was used, ill ustrates the effect of the beam refraction on the J = 0-1 and J = 2-1 lasing as a function of the atomic number.