Study of the mechanisms of spectral broadening in high power semiconductor laser arrays

High power semiconductor laser arrays have found increased applications in pumping of solid state laser systems for industrial, military and medical applications as well as direct material processing applications such as welding, cutting, and surface treatment. Semiconductor laser array products are required to have narrow spectral width for applications. Increasing the spectral accuracy by reducing the spectral width of the pump diode enables the laser system designer to improve the laser system compactness, efficiency, power, and beam quality while at the same time reducing thermal management cost in the system. Spectral width is one of the key specifications of laser array products and it is very important to improve the spectral performance to improve production yield, reduce cost and gain competitiveness. In this paper, we study the mechanisms of spectral broadening in high power semiconductor laser arrays.