Long Distance Propagation of UV Light Filaments in the Atmosphere

"Limited research has been performed on TW pulse propagation in the atmosphere, and the work that has been performed has focused on sources in the infrared over relatively short propagation distances. The purpose of this effort is to develop a high-power UVlaser system to extend the propagation distance of light filaments, called light-strings, in the atmosphere, and explore military and commercial applications associated with this novel technology. The Phase-I effort has extended our knowledge of pulsepropagation effects in the atmosphere, and has paved the way for the development of new innovative laser and lidar systems to produce and exploit long-distance light filamentation. In Phase-II, we will construct and field-test a high-power UV transmitterfor the purpose of demonstrating long-distance pulse propagation in the atmosphere. The long-term commercialization goal of this project is to develop commercial and military hardware to produce and exploit long-distance light filaments in the atmosphere.Potential applications of light-strings are: (1) lidar sources for measuring the density and distribution of molecular and chemical species in the atmosphere; (2) generating plasma channels for controlled lightning discharge; and (3) generating precisionpoint sources for use as guidestar beacons in adaptive optics systems. Light filaments have potential military utility in chemical and biological stand-off detection, and laser weapons delivery systems (adaptive optics)."