Abstract

To reduce energy losses by thermalization of charge carriers in a silicon solar cell, quantum-cutting luminescent materials are desired for the efficient downconversion of UV–visible radiation into near-IR radiation. In this Letter, quantum cutting involving emission of two near-IR photons for each UV-blue photon absorbed is demonstrated in ${\mathrm{Nd}}^{3+}∕{\mathrm{Yb}}^{3+}:\beta \text{-}\mathrm{Y}{\mathrm{F}}_3$ nanocrystals embedded in transparent bulk-glass ceramics. Upon excitation of an ${\mathrm{Nd}}^{3+}$ ion with a UV-blue photon, ${\mathrm{Yb}}^{3+}$ ions emit two near-IR photons through an efficient two-step energy transfer from ${\mathrm{Nd}}^{3+}$ to ${\mathrm{Yb}}^{3+}$ with ${\mathrm{Nd}}^{3+}:{}^4\mathit{F}_{3∕2}$ acting as the intermediate state.

© 2010 Optical Society of America