Optical Gain of InGaAlAs Quantum well with Different Barriers, Claddings and Substrates

Abstract

The fundamental characteristic of the quantum well heterostructures is the optical gain. In this paper, the effect of barriers (InGaAlAs and AlGaAs), claddings (InAlAs and AlGaAs) and substrates (InP and GaAs) materials on the optical gain of InGaAlAs quantum well of 6 nm width has been studied with in TE and TM polarization modes. The overall size (width) of the STIN-SCH (step index – separate confinement heterostructure) based nano-heterostructure including single quantum well along with barrier and claddings is 36 nm. In TE mode, the maximum optical gain for nano-heterostructure consisting of single quantum well (SQW) of InGaAlAs material with barriers of InGaAlAs and claddings of InAlAs is found at 1.55 µm wavelength; while for the SQW of the same material with barriers of AlGaAs and claddings of AlGaAs is found at 0.84 µm. For both types of heterostructures, the maximum gain corresponding to lasing wavelengths have been plotted on logarithmic scale and discussed. In order to support the obtained optical gain, the anti-guiding factors for both the structures have also been discussed.