Comparative VUV Synchrotron Excitation Study of YAG: Eu and YAG: Cr Ceramics

Using synchrotron radiation, a comparative VUV excitation study of YAG ceramics doped with Eu³⁺ and Cr³⁺ ions under VUV excitation (10.5–3.7 eV) at 9 K was conducted in this work. Both ceramics exhibit distinct excitation peaks in the VUV region, indicating high-energy transitions related to the internal electronic levels of the dopants and interband transitions within the YAG matrix. For YAG:Eu, the main excitation peaks at 6–7 eV correspond to transitions within the 4f-shell of Eu³⁺ and Eu³⁺-O²⁻ charge transfer states, showing weak dependence on the crystal field and high energy conversion efficiency. In contrast, YAG:Cr shows broad excitation bands due to transitions between levels influenced by strong crystal field interactions, resulting in lower luminescence efficiency. The study highlights the importance of crystal structure and dopant interactions in determining the spectral characteristics of YAG-based ceramics, offering potential for their application in advanced optoelectronic devices.