Effect of Impurity Position on Theoretical Performance of GaAsP/GaAs Quantum-Well Intermediate-Band Solar Cells under Concentrated Light

This study presents a numerical study of a GaAsP/GaAs quantum-well intermediate band solar cell with a single impurity located either at the center of the well or at the left/right barriers. The influence of impurity position on short-circuit current density and energy conversion efficiency was evaluated under varying levels of solar concentration, from natural sunlight to full solar concentration (FSC). The highest conversion efficiencies were obtained when the impurity was located at the center of the quantum well, with theoretical values of 44.31% under 1 sun (fs=1), 56.16% under high solar concentration regime (fs=1000), and 62.778% under FSC (fs=46296). In contrast, configurations with the impurity in the barriers exhibited slightly lower performance. Furthermore, the increase in efficiency under FSC conditions was notably higher than values reported in previous studies for GaAs-based cells, highlighting the beneficial effect of impurity inclusion and quantum well configuration on the photovoltaic response under concentrated light. Additionally, the results reveal that the efficiency remains stable across a range of quantum well widths, particularly when the impurity is placed at the center, emphasizing the robustness of this configuration under concentrated illumination conditions.