Highly efficient quantum cutting in Yb/Pr-codoped NaY(WO4)2 crystal

Cutting one ultraviolet photon into three near-infrared (NIR) photons can effectively improve the efficiency of silicon solar cells. We prepared Yb-doped, Pr-doped, and Yb/Pr-codoped NaY(WO4)2 (NYW) crystals. The Yb/Pr-codoped sample can divide the ultraviolet and blue photons into ∼1000 nm NIR photons, which brings strong emission at the NIR wavelength range. On the basis of the luminescence spectra and lifetime analysis, the quantum efficiency of the material is higher.