Strain-induced performance improvements in long-wavelength, multiple-quantum-well, ridge-waveguide lasers with all quaternary active regions

A comparison between the performance of strained (1.5% compression) and unstrained multiple-quantum-well (MQW), ridge-waveguide lasers with identical geometrical structures and similar emission wavelengths is reported. Results show that significant improvements in the characteristic temperature (T/sub 0/), maximum output power, maximum operating temperature, and internal quantum efficiency can be obtained through the applications of strain. Accordingly, for lasers employing strained active regions, an improved characteristic temperature, T/sub 0/, of 85 K and high-maximum lasing temperature of 140 degrees C were obtained under pulsed operating conditions. These values are the highest ever observed for long-wavelength lasers with all-quaternary strained MQW active regions. >