DARPA-NRL laser program. Report to Defense Advanced Research Projects Agency

The DARPA-NRL Laser Program is concerned with the development of laser technology in three project areas: chemical infrared lasers, electrical infrared lasers and electronic-state lasers. The chemical infrared laser program includes studies of pulsed HCl laser systems and molecular energy transfer processes. Data have been collected which suggests that intramolecular energy transfer occurs in SF6 at a rate 1,000 times the gas kinetic collision rate. The electrical infrared program emphasizes electric-discharge gasdynamic lasers and electron-beam pumping of potential laser systems in the mid-infrared. Several new energy transfer lasers have been discovered and a detailed discussion of the study of direct excitation HCl lasers is given. A number of excitation approaches are being evaluated for application to electronic state gas lasers. A most important step in the development of rare-gas halide lasers is the reporting here of the operation of XeF and KrF lasers in self-sustained discharges. Chemical pumping of atomic states is shown to lead to sufficient population for lasing and related quenching studies are described. Transverse discharge excitation of metal vapor lasers has been reduced to practice and coherent anti-Stokes Raman spectroscopy is being developed for probing the number density and vibrational temperature of gaseous species in a lasing medium.