Low threshold solar-pumped iodine laser

Solar-pumped lasing of i-C3F7I and n-C4F9I has been achieved at very low threshold pumping powers (170 solar constants) using a long (60 cm) gain length box laser configuration. Two xenon arc solar simulators were used to provide an AMO spectrum over the 60 cm gain length. Maximum pulse energy of 73 mJ and average power of 525 mW were achieved at 7.3 kW optical input. A slope efficiency of 0.074 percent was measured, the maximum theoretical efficiency being 0.2 percent. Longer gain lengths allow reduced optical input concentration, thus making the solar trough collector feasible for space applications, n-C4F9I was found to have less quenching of I*, making it a superior lasant to i-C3F7I.