Thermoreflectance-based measurements of facet optical absorption in aged high-power diode lasers (Conference Presentation)

Light absorption at the facet of a high power diode laser can lead to severe heating and catastrophic optical damage. In this work, a combination of high resolution thermoreflectance imaging and a detailed heat transport model of the diode chip are used to measure facet absorption in diode lasers. This approach permits a direct measurement of the effectiveness of passivation layers in improving facet robustness and device lifetime. The ability to quantify facet absorption is an essential step toward enabling rapid development of alternative passivation technologies and improving the reliability and maximum output power of diode laser systems.