SBIR-STTR Award

This Small Business Research (SBIR) Phase I project will determine the feasibility of scaling Yb:KGW based lasers to high powers and high beam quality through well controlled crystal growth of high quality crystals, accurate measurement of critical materials properties, and extrapolation of performance and manufacturability. Ytterbium (Yb) doped lasers are appealing for high power applications due to efficient diode pumping by commercially available diode lasers in the 900-980 nm spectral range. Yb:KGW is interesting in that high Yb doping concentrations are achievable. More significant are the unique properties of efficient self-cooling through anti-Stokes fluorescence and beam cleanup through stimulated Raman scattering. Another application exploits the wide emission bandwidth for mode-locked femtosecond pulses of high peak power leading to new sources for nonlinear spectroscopy and commercial high power pulsed sources. Critical data required to extrapolate the effectiveness of power scaling Yb:KGW lasers have been obtained from crystals of variable quality and from a limited subset of possible crystal compositions. The broader impacts of this technology would be for commercial solid state laser systems. Significant advances in the fields of industrial, medical, and research laser applications can be anticipated. Power scaling and reduced thermal management requirements lead to more efficient and lower cost high power 1m industrial lasers used in materials processing (cutting, welding, marking). Medical laser applications include therapeutic and surgical lasers, and picosecond pulse hard tissue dental lasers. Direct diode pumping allows for simple mode-locked ultrafast systems with reduced complexity and cost over conventional argon ion or frequency doubled Nd:YAG-pumped Ti:sapphire systems. In addition, the 1m mode-locked operation extends beyond the 900 nm limit of Ti:Sapphire creating new possibilities for optical parametric oscillator pump sources.

This Small Business Innovation Research (SBIR) Phase II project focuses on developing methods to improve the power and performance of an exciting new diode-pumped solid-state laser crystal. Laser crystals are superior to any other candidate material in the emerging and rapidly developing field of ultrafast lasers by their ability to generate high power femtosecond pulses. The proposed program will involve crystal growth in order to select the material with optimum operating performance and power handling capabilities. Issues to be addressed include the optimum concentration in the crystals, the uniformity of dopant incorporation during crystal growth, the preferred orientation of the crystal for laser rod fabrication, and methods to improve the quality and reliability of these crystals. The first commercial ultrafast laser system based on this technology was recently introduced. In order to ensure the rapid development of this new technology and the myriad applications in material processing, medicine and basic science it will undoubtedly enable, considerable development effort is required. This research effort is directed toward bringing the material system on which the laser is based to a point of performance, reliability and producability necessary for the commercial success of this new device