Spot-size converted 1.3 µm laser with butt-jointedselectively grown vertically tapered waveguide

Abstract
A 1.3 µm laser has been developed with a butt-jointed selectively grown spot-size converter (SSC). The SSC, vertically tapered waveguide and strained multiquantum well (MQW) active region are independently optimised. The laser was buried with semi-insulating InP to reduce optical loss in the SSC. A threshold current of 7 mA and an output power of > 20 mW were obtained. Minimum coupling loss to a flat-end fibre of 1.06 dB was achieved. Long-term stability was also confirmed.