Characteristics of top-surface-emitting GaAs quantum-well lasers

Self-aligned top-surface-emitting vertical-cavity GaAs four-quantum-well lasers emitting at 850 nm with good room temperature CW characteristics are discussed. Deep buried damaged layers by proton implantation are used to control vertical conductivity profiles for efficient current injection at the active region. Minimum CW threshold is 1.8 mA. Maximum CW output power is 1.5 mW. Laser linewidth of 0.02 AA is measured using a scanning Fabry-Perot etalon. For all sizes of lasers, the full angle beam divergences of fundamental transverse modes are twice as large as those calculated from a diffraction formula using aperture diameters.<
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