Linear and Nonlinear Optical Properties of GaAs/AlxGa1-xAs Multi-Shell Spherical Quantum Dot

Abstract

In this work, the optical properties of GaAs/AlxGa1-xAs/GaAs/AlyGa1-yAs multi-shell quantum dot heterostructure have been studied as a function of Al doping concentrations for cases with and without a hydrogenic donor atom. It has been observed that the absorption coefficient strength and/or resonant absorption wavelength can be adjusted by changing the Al content of inner-barrier and/or outer-barrier regions. Besides, it has been shown that the donor atom has an important effect on the control of the electronic and optical properties of the structure. The results have been presented as a function of the Al contents of the inner-barrier x and outer-barrier y regions and probable physical reasons have been discussed. (c) 2013 AIP Publishing LLC.