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Published August 19, 2020 | public
Journal Article

Photonic Crystal Waveguides for >90% Light Trapping Efficiency in Luminescent Solar Concentrators


Luminescent solar concentrators are currently limited in their potential concentration factor and solar conversion efficiency by the inherent escape cone losses present in conventional planar dielectric waveguides. We demonstrate that photonic crystal slab waveguides tailored for luminescent solar concentrator applications can exhibit >90% light trapping efficiency. This is achieved by use of quantum dot luminophores embedded within the waveguide that absorb light at photon energies corresponding to photonic crystal leaky modes that couple to incoming sunlight. The luminophores then emit at lower photon energies into photonic crystal bound modes that enable highly efficient light trapping in slab waveguides of wavelength-scale thickness. Photonic crystal waveguides thus nearly eliminate escape cone losses, and overcome the performance limitations of previously proposed wavelength-selective dielectric multilayer filters. We describe designs for hole-array and rod-array photonic crystals comprised of hydrogenated amorphous silicon carbide using CdSe/CdS quantum dots. Our analysis suggests that photonic crystal waveguide luminescent solar concentrators using these materials these can achieve light trapping efficiency above 92% and a concentration factor as high as 100.

Additional Information

© 2020 American Chemical Society. Received: April 13, 2020; Published: June 19, 2020. This work was supported by the DOE "Photonics at Thermodynamic Limits" Energy Frontier Research Center under Grant DE-SC0019140 (D.R.N. and M.P.) and also by the by the Caltech Space Solar Power project (H.C.B.). Work by C.R.B., W.W., and Z.C.H. were supported in part by the Engineering Research Center Program of the National Science Foundation and the Office of Energy Efficiency and Renewable Energy of the Department of Energy under NSF Cooperative Agreement No. EEC-1041895. Author Contributions: H.C.B. and C.R.B. contributed equally to this work. The manuscript was written through contributions of all authors. The authors declare no competing financial interest.

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August 19, 2023
October 20, 2023