SBIR Phase I:Rare-Earth-Doped Wavelength Conversion Material and Optical Element

This Small Business Innovation Research (SBIR) Phase I project aims to integrate up and down conversion materials into a single photonic device to solve the problem of mismatch between the solar spectrum and solar cells formed from single absorbers such as silicon. Cooperative nonradiative energy transfer between rare-earth dopants will be employed as the physical mechanism to support wavelength conversion. By integrating up and down converting materials, this approach will not only enhance quantum efficiency above and below the absorber band gap, but also recover losses associated with down conversion in the up converter. In this project, fluorine-based materials developed for solid state lasers will be doped specifically for solar applications, and will be tested to determine the feasibility of efficient synergistic up and down conversion between 1 and 1000 suns. The broader/commercial impact of this project will be the potential to significantly improve energy conversion efficiency of solar cells. The spectrum mismatch addressed in this work is responsible for the loss of 50% of the energy reaching solar cells. In addition, this technology does not require changes to the solar cells or electrical connections. Therefore, the integration of this optical product into solar energy systems is straightforward.