High-Power Tapered Photonic Crystal Lasers With Slots for Narrow Spectral Width

High-power low-divergence tapered lasers with slots in the ridge waveguide section and near the front facet are demonstrated and compared. Both devices can achieve a narrow spectral width. Tapered lasers with slots in the ridge waveguide deliver an output power of 2.15 W with a wall-plug efficiency of 43%. The maximum side mode suppression ratio (SMSR) is 28.8 dB and the vertical far-field angle is around 11°. For tapered lasers with slots near the front facet, the output power and the wall-plug efficiency are 1.87 W and 37%, respectively. An SMSR of 36.8 dB and a vertical beam divergence of 7° are obtained. High beam quality is achieved for both devices.