Single transverse mode 850 nm GaAs/AlGaAs lasers with narrow beam divergence

摘要

GaAs/AlGaAs 850 nm range lasers based on a longitudinal photonic bandgap crystal waveguide show narrow vertical far-field pattern. Vertical and lateral beam divergence with FWHM below 10° and 5°, respectively, is demonstrated for 4 μm stripe width, being independent on injection current. Excellent beam quality with M~2 = 1.4, low internal losses of 1.4 cm~(-1) and high differential quantum efficiency of 83% are observed.