Limiting Efficiencies of Multijunction Solar Cells With Multiple Exciton Generation

The introduction of multiple exciton generation (MEG) processes with a low maximum quantum yield (QY) (maximum 200%) into a multijunction solar cell provides an efficiency increase up to 4.2% absolute for a triple-junction solar cell under concentration. In addition, the efficiency contour plots show increased flexibility in material choices, even for series connected devices. Importantly, the MEG QYs necessary to achieve these advantages are moderate and within experimental measured values, requiring no more than the generation of two electron hole pairs from a photon.