Structure–property correlations in Ce-doped garnet phosphors for use in solid state lighting

The discovery of inorganic phosphors that can be excited by GaN light emitting diodes in the wavelength range 380–460 nm is essential for improving the efficiency and light quality of solid state lighting devices. Garnets doped with Ce3+ are of particular interest for this application. We have studied the luminescence of Ce3+ in garnet phosphors and established a relationship between the excitation/emission wavelengths and the deviation from cubic symmetry around the rare-earth ion. Data are presented for both known yttrium aluminum and yttrium gallium garnet systems, as well as newly synthesized inverse garnets of the general formula Mg3Y2−yGdyGe3−zSizO12:Ce (0 ⩽ y ⩽ 2, z = 0, 1).