Observation of vacuum-ultraviolet Kr(2)* laser oscillation pumped by a compact discharge device

We have demonstrated vacuum-ultraviolet (VUV) Kr(2) * laser oscillation as a result of the realization of a stable self-sustained discharge of high-pressure Kr by use of a compact discharge device. Glow discharge was obtained with as much as 10 atm of pure Kr. The VUV emission intensity centered at 147.8 nm abruptly increased when the charging voltage exceeded a certain value. In addition to this threshold behavior, considerable spectral narrowing (4.0?0.4 nm) was observed when the charging voltage increased. The maximum output energy at 148 nm was 150muJ . The gain coefficient was estimated to be 1.1% cm (-1) .