Quantum size effects in nanostructures: Engineering the optical properties of quantum dots

We present theoretical studies for the quantum size effects on the charge carrier's energy levels in different volumes of AlxGa1-xAs cubic and spherical quantum dots for an infinite potential barrier. A fundamental objective is to explore the role of doped material in semiconductors and investigate the quantum size effects to engineer the optical and electronic behavior of quantum dots, to be widely used in electronics and optical devices. Calculations investigated that the effective de-Broglie wavelengths of the charge carriers decrease with increasing temperatures. For the energies of the ground state (E1) and the first two excited states (E2, E3), we indicated that the energy value in a spherical is less than its value in cubic quantum dots by values (E1∼0.866), (E2∼0.886) and (E3∼0.982). The emitting colors from the two quantum dots with increasing volume for x values are as follows; x = 0 (orange-red-infra-red), x = 0.2 (green-orange-red), x = 0.4 (green-yellow-orange-red), x = 0.6, (blue-green), and x = 0.8 (violet-blue-cyan-green).