SBIR-STTR Award

We propose a fundamental study of filamentation in air that will combine the theoretical expertise at the University of Arizona in simulating these nonlinear phenomena, the experimental facilities at the University of New Mexico in ultrafast diagnostics, and the experience at Lite Cycles, Inc. in the design and construction of high-power, short-pulse lasers. In Phase I of this program, we will make measurements of air parameters at various wavelengths to refine the simulation. We will perform direct spatio-temporal measurements on IR and UV filaments by letting them diffract in a vacuum chamber sealed by an aerodynamic (supersonic) window. This technique will enable us to make measurements on pulse parameters inside the filament, which are not affected by nonlinear effects usually occuring at a solid reflecting interface. We expect that the combination of measurements and simulation will enable us to get a complete understanding of the self-trapping mechanism in air, and thus select the best wavelength to be used in Phase II of the program.This project will have applications in creating a remote bright point source for lidar applications as well as for wavefront correction..

Keywords:
Light Strings;Filaments;Self-Induced Waveguides;Guided Energy;Laser Trapping;

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 UV laser 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 pulse propagation 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 transmitter for 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 precision point 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).

Keywords:
LIGHT STRINGS, FILAMENTS, SELF-INDUCED WAVEGUIDES, GUIDED ENERGY, LASER TRAPPING