Advancements in GaN-based high-power edge-emitting lasers for the blue and green spectral range

GaN-based high-power visible laser diodes are a key enabling technology for next-generation projection systems and a wide range of other optical applications. In this work, we present recent progress in the development of edge-emitting multimode lasers operating in the blue spectral region, with a focus on a central wavelength of 455 nm. Through optimization of the waveguide structure and chip design, we achieved significant improvements in both optical output power and power conversion efficiency (PCE). Packaged in a productive multi-die cluster and operated at 3.5 A in continuous-wave mode and room temperature, the optimized high-power lasers demonstrate a PCE exceeding 50% and output powers up to 6.75 W per laser. The highest recorded PCE at 453 nm is 51.5%. We will also discuss data on temperature-dependent performance and reliability. Further developments will be presented including lasers emitting at shorter wavelengths in the range of 440 nm which are particularly suited for material processing and other industry applications. In addition, we report on the development status of high-power green GaN lasers. Targeting a central wavelength of 525 nm, we present performance data across the range from 515 nm to 538 nm. Depending on wavelength, these devices achieve output powers exceeding 1.9 W and a PCE above 24% at 2 A and room temperature.