Wide-Stripe Distributed Bragg Grating Lasers With Very Narrow Spectral Linewidth

Gain-guided lasers with distributed Bragg reflector gratings that exhibit narrow emission linewidths of under 500 kHz are demonstrated. Partial coverage of a facet with a grating is found to be sufficient to ensure single-wavelength laser operation. Narrow linewidth operation in 40 and 150-μm wide lasers with partial gratings is demonstrated. The use of antireflection coatings to suppress spurious Fabry-Perot modes is also presented. Linewidths as low as 200 kHz that are insensitive to drive current are observed.