Gain saturation and the efficiency of energy conversion into radiation in a supersonic oxygen-iodine laser with a stable cavity

An experimental investigation was made of the optical gain saturation in a supersonic oxygen-iodine laser with a stable cavity. The measured saturation intensity, 15 kW cm(-2), was close to that calculated for homogeneous saturation of the gain line and for a finite rate of mixing of the hyperfine-structure levels of the iodine atom. The reported calculations and experiments showed that the transfer of energy from oxygen to iodine and mixing of the hyperfine I((2)P(1/2)) sublevels set limits on the conversion of the stored energy into radiation in a laser with a finite length of the mirrors along the gas-flow direction.