Comprehensive Analysis of Mode Competition in High-Power CW-Operating Diode Lasers of the Antiresonant Reflecting Optical Waveguide (ARROW) Type

Three-dimensional above-threshold analyses have been performed on laterally antiguided laser structures of the antiresonant-reflecting-optical-waveguide (ARROW) and simplified (S)-ARROW types, of relatively large core width (10 μm), for generating watt-range continuous wave (CW) powers in a single, stable spatial mode. The 3-D numerical code takes into account carrier diffusion in the quantum wells, thermo-optic effects as well as edge radiation losses. The behavior of both device types is studied over a wide range in the variation of the width of the high-index regions s bordering the low-index device core. The results of the analyses indicate that thermal lensing plays an essential role in optical-mode competition. Best results (i.e., single-mode CW powers in excess of 1.5 W) are obtained when s corresponds to a lateral resonant condition. When s corresponds to one full lateral wave, both ARROW and S-ARROW devices reach CW single-mode powers of 1.7 W. When s corresponds to about one half lateral wave, both ARROW and S-ARROW devices display isolated regions of modal instability followed by CW operation in a stable, single spatial mode to powers as high as 2.0 W.