This property makes quantum dots attractive for multi-junction solar cells, where a variety of materials are used to improve efficiency by harvesting multiple portions of the solar spectrum.
By developing a library of these co-doped materials with different optical band gaps, it may be possible to engineer a multi-junction solar cell with excellent efficiency absorbing visible light.
For different parts of the light spectrum, different materials work better than others -- which is why multi-junction solar cells can achieve such high conversion rates.
Concentrating photovoltaic systems leverage the cost of high efficiency multi-junction solar cells by using inexpensive optics to concentrate sunlight.