Tunable subnanosecond pulse generation in a dye laser using overlapped pump pulses

We report a simple technique for generation of tunable subnanosecond pulses (0.2–0.4 ns) based on single spike selection from the relaxation oscillations in a dye laser using preformed and overlapping in time excitation pulses. The pulses were obtained by temporal division of a 5–50 ns initial pulse using a Pockels cell with a 1–2 ns switching time and an optical delay time. The proposed technique widens the choice of suitable dye lasers in which the single spike selection technique may be applied, to include dye lasers excited by a Q-switched solid-state laser or a Cu-vapor laser. Other advantages to this technique are the shortened length of the generated subnanosecond pulse, the increased energetic output, higher reproducibility, and the possibility for synchronization of spike generation to an external signal accurate to within 2–3 ns.