Edge-emitting Nitride-based Bragg Reflector Lasers

In this program we will develop narrow linewidth AlGaN Bragg reflector lasers suitable as injection seeds for solid-state W lasers in the range of 280 to 330 nm. These systems are compact, light weight, and low-power consuming and ideal for airborne lidar systems. Bragg reflector lasers have never been fabricated in the nitrides so in this Phase I program we will develop the technologies necessary to fabricate an AlGaN Bragg reflector laser. The Phase I program includes the determination of the growth conditions necessary to grow n- and p-type doped AlGaN, fabrication of gratings in GaN necessary to form the Bragg reflector, and reduction of the p-type GaN ohmic contact resistivity which is necessary for efficient laser operation. In Phase II we will combine the learned processes to fabricate an AlGaN Bragg reflector laser suitable as injection seeds for solid-state W lasers. ATMI, along with our subcontractor at the University of Illinois, is uniquely suited to develop AlGaN Bragg reflector lasers as ATMI is a recognized leader in nitride material growth and Illinois is a leader in the development of narrow-linewidth DFB and DBR lasers. Development ot a compact, high efficiency blue / W laser will have wide ranging impact with major applications for these lasers including high density optical storage and communications. Short wavelength excitation sources will be used for spectroscopic applications ranging from blood chemistry analyses to exhaust gas monitoring.