Electronic and optical properties of 1.55 μm GaInNAs/GaAs quantum-well structures

The electronic and optical properties of 1.55 μm GaInNAs/GaAs quantum-well (QW) lasers are investigated using the multiband effective-mass theory. The results are compared to those of 1.3 μm GaInNAs/GaAs QW lasers. The QW structure with a wavelength of 1.55 μm has a smaller strain in the well than that with a wavelength of 1.3 μm. The 1.55 μm QW structure is shown to have a smaller optical gain than the 1.3 μm QW structure. This is mainly attributed to the fact that the former has a smaller matrix element and a larger average effective mass than the latter. However, the difference in the optical gain between the two QW structures is greatly reduced with increasing well width. In the case of a QW structure with a well width of L_w = 80 Å, the optical gain of the QW structure with a wavelength of 1.55 μm is found to be similar to that of the QW structure with a wavelength of 1.3 μm.