Monolithic spectral stabilization is demonstrated in narrow-stripe broad-area lasers (NBA) with high power (5W), conversion efficiency (50%) and high brightness, by using optimized high-order surface-etched DFB gratings. However, surface etched gratings introduce a high index contrast into the semiconductor, leading to the scattering losses increasing rapidly with groove etch depth, limiting efficiency and yield. We therefore review progress in the exploitation of novel, non-uniform grating configurations for improved performance. Devices with non-uniform gratings whose groove etch depth decreases toward the front facet (apodized grating) are shown to operate with enhanced spectrally stable power (6W) compared to devices with uniform gratings.

© 2017 COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

J. Decker, J. Fricke, A. Maaßdorf, G. Erbert, G. Tränkle, and P. Crump, "Non-uniform DFB-surface-etched gratings for enhanced performance high power, high brightness broad area lasers," Proc. SPIE 10086, High-Power Diode Laser Technology XV, 100860R (Presented at SPIE LASE: January 31, 2017; Published: 22 February 2017); https://doi.org/10.1117/12.2251835.