Multi-Junction Solar Cell Spectral Tuning with Quantum Dots

We have theoretically analyzed the potential efficiency improvement to multi-junction solar cell efficiencies which are available through the incorporation of quantum dot using detailed balance calculations. We have also experimentally investigated the Stranski-Krastanov growth of self-organized InAs quantum dots and quantum dot arrays on lattice-matched GaAs by metallorganic vapor phase epitaxy (MOVPE). The morphology of the quantum dots were investigated as a function of their growth parameters by atomic force microscopy (AFM). Photoluminescence and optical absorption measurements have demonstrated that the incorporation of InAs quantum dots (QD) into a GaAs structure can provide sub-GaAs bandgap electronic states