Sensitivity of lasing in neonlike zinc at 212 nm to the use of the prepulse technique

We report strong lasing in zinc on the neonlike 3p → 3s, J = 0 → 1 transition at 21.2 nm when the prepulse technique of using a low-intensity prepulse before the main optical drive pulse is used with the 1.315-μm Asterix laser to illuminate the zinc target. Without the use of the prepulse, this line is not visible. The usual J = 2 → 1 lines at 26.2 and 26.7 nm are observed weakly both with and without the use of the prepulse. By variation of the prepulse energy, we demonstrate that even a very weak prepulse with less than 0.1% of the main pulse energy can enable the zinc to lase at 21.2 nm.