1.56 µm InGaAsP/InP tapered active layer multiquantumwelllaser with improved coupling to cleaved singlemode fibre

Abstract
The authors report 1.56 µm MQW BH lasers that use a tapered active region and underlying passive guide to increase the laser spot size. Coupling losses to 10 µm core cleaved singlemode fibre as low as 4.7 dB have been obtained for devices with threshold currents of ~12 mA at 20°C.