Synchronization of dual-line lasing and subsequent gigahertz modulation of iodine lasers through mode locking

Dual hyperfine line lasing of a Zeeman-tuned photolytic iodine laser resulting in 14-GHz modulated laser radiation was studied experimentally and theoretically as a function of the applied magnetic field. Synchronization of the phases of the two hyperfine lines necessary for optimum gigahertz modulation was achieved by mode locking. The resulting pulse durations of 740 ps were shorter than those previously observed without a magnetic field. Short pulses, together with the possibility of scaling the results to high-power chemical-oxygen iodine lasers, make this concept attractive for a laser-driven ultrawideband microwave source.