Effect of capping layer of GaAlAs on the electronic and optical properties of GaAs spherical layer quantum dot

In the framework of effective-mass envelope function theory, we present a theoretical investigation of the electronic and optical properties for a system of nano layer consisting of spherical nano layer of GaAs (core) with capping layer of GaAlAs (shell). An exact analytical solution of the corresponding Schrödinger equation is obtained; in addition to that a transcendent equation for determination of electron energetic spectrum is derived as well. Dependences of the electron energy, threshold frequency and absorption coefficient versus the external radius, and the thickness of the capping layer are presented. The results showed that the electronic and the optical properties strongly depended on the thickness of the capping layer. We expect that such systems may be significant for practical application.