Optical property of a novel (111)-oriented quantum structure

Abstract
A novel hetero tensile-unstrained-tensile-unstrained-tensile (t-u-t-u-t) quantum structure, which consists of multiple quantum wells in the unstrained ( u ) regions, lattice matched to a (111)-oriented substrate, and sandwiched between tensile-strained epitaxial layers ( t ), is proposed. The energy band configuration modified by the strain-induced piezoelectric field and the distribution of the built-in internal electric field within this hetero t-u-t-u-t quantum structure were theoretically deduced and found to be consistent with the experimental results. It was demonstrated that some nonlinear optical properties such as the energyblue shift observed in the excitation-power-dependent photoluminescence spectra are strongly dependent on the distribution of the strain-induced built-in electric field within this quantum structure and quite comparable to the analogous values for the existing quantum structures.