Progress towards high efficiency thin-film III-V quantum dot solar cells for space

This work summarizes our results in the development of high efficiency III-V quantum dot (QD) solar cells, aimed at tackling with two of the most relevant issues posed by QD solar cells (QDSCs), namely the degradation of open circuit voltage and the weak photon harvesting by QDs. In particular, we report our latest achievements in: i) The molecular beam epitaxy growth of high-quality QDSCs, demonstrating Voc as high as 0.94 V and low penalty (~ 40 mV) with respect to the single-junction reference cell. ii) The development by nanoimprint lithography of metal/polymer back reflectors with high diffraction efficiency, enabling four times increase of the QD photogenerated current. Experimental results are discussed with the support of numerical simulations.