Stimulated Raman scattering in lead vapor heat pipe for tunable and narrow-linewidth XeCl excimer laser

Narrow-linewidth and high-efficiency conversion of stimulated Raman scattering in a lead vapor heat pipe was observed using a narrow-linewidth and injection-locked XeCl excimer laser system as the pump source. The XeCl was continuously tuned over its entire B-X gain curve, from the (0-0) transition to the (0-3) transition, giving it a range of 0.8 nm (307.65-308.45 nm). The laser linewidth was narrowed down to 0.002 Å(0.02 cm^-1). The output energy was 310 mJ/pulse, with a repetition rate up to 50 p.p.s. and good beam quality. A lead vapor heat pipe operating at 1225°C was used as a single-pass stimulated Raman converter, shifting the radiation from 308 to 459 nm. Photon conversion efficiency as high as 80% was achieved, using a pump linewidth of 0.01 Å.