Double-asymmetric-structure 1.5 μ m high power laser diodes

Design considerations for high pulsed power and brightness 1.5 μm laser emitters for laser radar applications, based on comprehensive semi-analytical theory, are presented. A strongly asymmetric waveguide design with a bulk active layer positioned very near the p-emitter interface is chosen to minimize the current-induced losses at high power while maintaining a single, broad transverse mode. Moderate to high doping of the n-side of the Optical Confinement Layer and high p-doping of the p-cladding layer are used to reduce the residual current-induced losses and the electric resistance of the structure. For pulsed room-temperature operation, short laser resonators are found to be advantageous. First experimental results are presented. An as-cleaved sample with a stripe width of 90 μm and a resonator 2 mm long exhibits an output power of about 18 W at a pumping current amplitude of 80 A, with 1 mm long resonators showing higher power output. Further improvements are predicted by structure optimization as well as increase in internal quantum efficiency and thermal performance.

Hallman Lauri, Ryvkin Boris S., Avrutin Eugene A., Aho Antti T., Viheriälä Jukka

A4 Article in conference proceedings

2019 IEEE High Power Diode Lasers and Systems Conference (HPD)

L. Hallman et al., "Double-asymmetric-structure 1.5 μ m high power laser diodes," 2019 IEEE High Power Diode Lasers and Systems Conference (HPD), Coventry, United Kingdom, 2019, pp. 19-20, doi: 10.1109/HPD48113.2019.8938671