Fig. 1. (a) Reflection spectrum for α=30  cm−1, (b) maximum reflectivity, (c) loss, and (d) transmission of 10th-order DBR sections with V-shaped grooves (assuming a laterally infinite grating) as a function of the length of the DBR section for different values of an additional modal absorption α.

Fig. 2. (a) Schematic side view of a DBR laser diode consisting of a gain section and a DBR section; top-view scanning electron microscope images of (b) the DBR laser chip before the SiO2 deposition and (c) the 10th-order surface gratings with V-shaped grooves.

Fig. 3. Optical power-current-voltage characteristics of DBR laser diodes with LDBR of 50, 100, and 200 μm for emission from (a) the front facet and (b) the rear facet.

Fig. 4. (a) Output power-current characteristic and (b) 2D colormap of emission spectra at different currents of a DBR laser diode with LDBR of 200 μm measured at the front facet. Inset: high-resolution emission spectra of the DBR laser diode at 105 mA.

Fig. 5. Temperature dependence of the peak emission wavelength of a DBR laser diode with LDBR of 200 μm operated at 100 mA.