High temperature operation with low-loss couplingto fibrefor narrow-beam 1.3 µm laserswith butt-jointed selective grown spot-size converter

High temperature operation is demonstrated for narrow-beam 1.3 µm lasers with butt-jointed selectively grown spot-size converters. Low thresholds of 5.6 mA and 15.8 mA at 25°C and 85°C and a maximum operating temperature of 134°C were obtained. Low loss coupling to fibre of <1.8 dB was achieved in the temperature range from 25°C to 85°C with an output power up to 30 mW.