Gain saturation coefficients of strained-layer multiple quantum-well distributed feedback lasers

The gain saturation coefficients were measured for strained and unstrained multiple quantum-well distributed feedback (MQW-DFB) lasers. The gain saturation coefficient depends on the deviation of the laser's transverse-magnetic (TM) mode gain peak wavelength from its transverse-electric (TE) mode gain peak wavelength delta lambda , which is related to the strain on the active-layer wells. The gain saturation coefficient epsilon increased with increasing compressed strain on the active-layer wells. The coefficient epsilon of the unstrained MQW DFB laser with a wavelength deviation delta lambda of -350 AA was 2.45 x 10/sup -17/ cm/sup 3/, and epsilon increased up to 12.6 x 10/sup -17/ cm/sup 3/ in the SL-MQW DFB laser with a wavelength difference delta lambda of -890 AA.