InAs/InGaAs MQW lasers emitting at 2.3 μm grown by MOVPE

InAs/InGaAs multiple-quantum-well (MQW) structures with good structural and optical properties on InP substrates were grown by metalorganic vapor phase epitaxy (MOVPE) and applied to the lasers emitting at wavelengths longer than 2.3 mum. InAs/InGaAs MQWs with flat interfaces were obtained by choosing a growth temperature between 460 and 500degC. The photoluminescence peak wavelength of the MQWs increases from 2.09 to 2.42 mum as the thickness of InAs quantum wells increases from 2.8 to 5.9 nm. The structural and optical properties remained almost unchanged even after annealing at 620degC. For a distributed feedback (DFB) laser with a buried heterostructure, a single-mode emission with wavelength of 2.330 mum was achieved under continuous-wave operation at 25degC. The maximum output power was 20 mW at 25degC, and the maximum operating temperature was as high as 85degC. The emission wavelength of the laser was finely controlled from 2.330 to 2.341 mum by adjusting the injection current and the operating temperature. The current-tuning and temperature-tuning rates of the DFB wavelength were +0.014 nm/mA and +0.141 nm/K, respectively.