High-power diode lasers with small vertical beam divergence emitting at 808 nm

A new waveguiding scheme for high-power diode lasers based on high-index quarter-wave reflecting layers inserted into the cladding layers is presented. For 808 nm lasers, a small vertical far-field angle of 18/spl deg/, a low threshold current density of 280 A/cm/sup 2/ and a high conversion efficiency of 50% are simultaneously obtained.