Energy levels of In_x Ga_(1-x) As/GaAs quantum dot laser with different sizes

Abstract

In this paper, we have studied the strain, bandedge, and energy levels of cubic InGaAs quantum dots (QDs) surrounded by GaAs. It is shown that overall strain value is larger in InGaAs-GaAs interfaces, and also in smaller QDs. Also, it is proved that conduction and valence band-edges and electron-hole levels are size dependent; larger QD sizes appeared to result in the lower recombination energies. Moreover, more number of energy levels separates from the continuum states of bulk GaAs and comes down into the QD separate levels. In addition, degeneracy of eigenvalues was found to be subjected to change by size variation. Our results coincide with former similar researches. Keywords: strain, bandedge, engineering energy levels, quantum dot size, QD laser