Interband emission energy in a dilute nitride quaternary semiconductor quantum dot for longer wavelength applications

Abstract

Excitonic properties are studied in a strained Ga1−xInxNyAs1−y/GaAs cylindrical quantum dot. The optimum condition for the desired band alignment for emitting wavelength 1.55µm is investigated using band anticrossing model and the model solid theory. The band gap and the band discontinuities of a Ga1−xInxNyAs1−y/GaAs quantum dot on GaAs are computed with the geometrical confinement effect. The binding energy of the exciton, the oscillator strength and its radiative life time for the optimum condition are found taking into account the spatial confinement effect. The effects of geometrical confinement and the nitrogen incorporation on the interband emission energy are brought out. The result shows that the desired band alignment for emitting wavelength 1.55µm is achieved for the inclusion of alloy contents, y=0.0554% and x=0.339% in Ga1−xInxNyAs1−y/GaAs quantum dot. And the incorporation of nitrogen and indium shows the red-shift and the geometrical confinement shows the blue-shift. And it can be applied for fibre optical communication networks.