fig4

Figure 4. (A) PLE spectrum of GAGG: 2at% Eu³⁺ ceramic; (B) Emission spectra of GAGG: xEu³⁺; (C) Schematic diagram of the Eu³⁺ photo-luminescence energy-level transitions; (D) Relationship between lg(I/x) and lg(x) for GAGG: xEu³⁺ ceramics. GAGG: Gd₃Al₃Ga₂O₁₂; PLE: photoluminescence excitation.