Perfluorobutyl iodides as gain media for a solar-pumped iodine laser amplifier

The effectiveness of t-C4F9I and n-C4F9I as gain media for a space-based solar-pumped iodine photodissociation laser is investigated experimentally. The optically coupled flashlamp/amplifier-tube apparatus described by Hwang et al. (1986) is employed, driving the amplifier with 4-microsec 4.2-mJ TEM(00) pulses from a flashlamp-pumped laser oscillator; the variation of amplification with energy-extraction time was monitored by inserting a delay of up to 1 msec between the firing of the two flashlamps and measuring the delay between the optical pulses. The results are presented graphically and briefly characterized. The performance of t-C4F9I is found to be better than that of n-C4F9I (or n-C3F7I), with an absorption band shifted toward the visible (for improved utilization of solar radiation), higher gain (by a factor of 2) at all delay times, and better chemical reversibility. The gain did not depend significantly on temperature in any of the iodides.