Narrow-band XeCl laser with an amplifier

An investigation was made of an electric-discharge XeCl laser consisting of a narrow-band master oscillator and an amplifier with an unstable resonator. Narrow-band radiation tunable in the 307.5–308.5 nm range with a line width of up to 1 pm and an angular divergence of 0.1 mrad was obtained. Up to 70% of the laser output power was concentrated in a narrow line.