Picosecond amplification and kinetic studies of XeCl

A 2 ps pulse derived by frequency doubling the amplified output of a CW mode-locked dye laser has been used to probe the gain characteristics of XeCl in the 308 nm region. Energy saturation parameters were measured for the four main laser transition. The gain kinetics of XeCl were investigated by observing the temporal gain recovery after the passage of a saturating picosecond pulse, and the contribution of the various relaxation processes to the XeCl gain dynamics is discussed. Evidence suggests that vibrational relaxation in the upper laser level is incomplete during the effective lifetime of XeCl*. Taken together, these measurements have permitted the determination of a stimulated emission cross section of general utility. To demonstrate the potential of XeCl for high power amplification, a picosecond pulse was amplified to a power of ∼20 GW.