For decades, solar-cell efficiencies have remained below the thermodynamic limits. However, new approaches to light management that systematically minimize thermodynamic losses will enable ultrahigh efficiencies previously considered impossible.

NPG
doi.org/10.1038/nmat3263
Nature Mater.
LMPV
Photonic Materials

Polman, A, & Atwater, H.A. (2012). Photonic design principles for ultrahigh-efficiency photovoltaics. Nature Mater., 11, 174–177. doi:10.1038/nmat3263