SINGLE-MODE OPERATION AND MODE LOCKING OF HIGH-PRESSURE CO2 LASERS BY MEANS OF SATURABLE ABSORBERS

Abstract
Single‐longitudinal‐mode operation of pulsed, high‐pressure, transversely excited CO2 lasers has been obtained by means of a saturable absorber (SF6) cell placed inside the laser cavity. Eighty percent of the multimode ouput power is obtained in the single‐mode output. Single‐mode operation has been verified by means of a scanning Fabry‐Perot interferometer. Pressure broadening of the saturable absorber by a buffer gas has been found to cause multimode mode‐locked operation of the laser.