Efficiency of an optically pumped XeF laser

An experimental investigation was made of the characteristics of a photodissociation laser operating on the B–X (353 nm) and C–A (485 nm) transitions of the excimer XeF. The laser was pumped with vacuum ultraviolet radiation from an open high-current discharge. The energy in a laser pulse and the average specific output energy reached values of respectively 28 J and 18 J/liter at 353 nm and 14.5 Jand 10J/literat485nm. Measurements were made of the instantaneous lasing efficiency, defined as the ratio of the laser output power to the electrical input power from the pump source. At the maximum of a laser pulse the efficiency reached 0.8% at 353 nm and 1 % at 485 nm (corrected for the geometrical utilization factor of the pump source radiation). It was established that the pump source efficiency was 7.5–8.5% and that the quantum efficiency of the formation of XeF(B) averaged over the pump band was 85 ± 5%. Ways of raising the laser efficiency to ~ 2% were considered.