SKM 2023 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 28: Focus Session: Breakthroughs in wide-bandgap semiconductor laser diodes II

HL 28.3: Vortrag

Mittwoch, 29. März 2023, 16:00–16:15, POT 251

Spectral dynamics of lateral modes and filaments in InGaN broad-ridge laser diodes — •Lukas Uhlig¹, Dominic J. Kunzmann¹, Anna Kafar^2,3, Szymon Grzanka^2,3, Piotr Perlin^2,3, and Ulrich T. Schwarz¹ — ¹Chemnitz University of Technology, Chemnitz, Germany — ²Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland — ³Top-GaN Ltd., Warsaw, Poland.

Blue InGaN broad-ridge laser diodes are versatile, efficient, and compact high power emitters, which are demanded for copper welding, white light generation, and other applications. Compared with standard narrow-ridge laser diodes, in case of the broad-ridge devices the ridge width is increased from around 2 µm to tens of micrometers, leading to lateral multi-mode operation or filamentation.

We investigate a series of devices with ridge widths from 2.4 µm to 20 µm and study their lateral-spectral-temporal behavior as well as high-resolution spectra. With increasing ridge width, we observe the transition from lateral single-mode to multi-mode operation and in the case of the 20 µm wide ridge, filamentation occurs. In the multi-mode regime, the dynamic onset behavior as well as the spectral-lateral mode distribution are governed by competition of lateral and longitudinal modes for gain. Filaments form in the case of strong nonlinear interaction between intensity, charge carrier density, temperature, and refractive index. Using high-resolution spectroscopy, we can clearly differentiate between different lateral modes, which occur in parallel and form multiple longitudinal mode combs.