Energy transfer and enhanced 1532 nm emission in Er and Ce co-doped Y3Al5O12 nano-particles

A series of Y₃Al₅O₁₂:Ce³⁺, Er³⁺ (YAG:Ce, Er) nano-particles were synthesized by polymer-assisted sol–gel method. X-ray diffraction measurements reveal that a pure crystalline phase of YAG is achieved at temperature as low as 800 °C. The energy transfer from Ce³⁺ to Er³⁺ is studied based on photoluminescence spectroscopy and fluorescence decay patterns. It results that the emission intensity of Er³⁺ at near infrared (NIR) 1532 nm under indirect excitation of Ce³⁺ (460 nm) is 10 times stronger than that of direct excitation of Er³⁺ (275 or 380 nm). The energy transfer efficiency is estimated as 95.5% for YAG:Ce_0.03Er_0.09 sample. The very efficient energy transfer path and mechanism are also discussed.