Optical telecommunication at 1.3 and 1.55 μm using dilute-nitride III-V semiconductors

We have compared the calculated band structure and optical gain of compressively strained InGaAsN quantum-well lasers emitting at 1.3 μm with GaAs or GaAsP barriers, grown on GaAs substrates. The higher band gap of GaAsP barriers yields a better hole confinement in the quantum well. We show that this can result in an increase of the material gain of more than 40 % at device operating temperature, which can be explained by the reduction of the hole leakage out of the quantum well. Dilute nitride structures also offer the possibility of growing tensile strained QW lasers on InP substrate emitting in the telecommunication L-band. We have calculated the characteristics of InGaAsN/InAsP/InP quantum well structures and compared to the ones of N-free quantum well structures. It appears that the introduction of a fraction of nitrogen as small as 0.003 allows to pass over the emission wavelength of 1.57 μm and induces an increase of the material gain by a factor of 3, partly due to the reduction of the electron leakage out of the quantum well.