Radio-luminescence and absence of trapping defects in Nd-doped YAG single crystals

Nd-doped yttrium aluminum garnet (NdYAG) is an important solid-state laser material due to Nd3+ inter-configurational transitions which result in intense infrared emission. This work shows that NdYAG crystals also emit visible radio-luminescence in response to exposure to beta particles due to other Nd3+ interconfigurational 4f-4f transitions. Additionally, thermo-luminescence spectroscopy reveals the absence of traps in NdYAG, making it a potentially superior scintillation material. The fact that Nd is present in only one valence state in NdYAG leads to charge balance and results in the suppression of defect formation. This finding reveals fundamental understanding regarding defect formation in ionic crystals. (C) 2012 Elsevier B.V. Open access under CC BY-NC-ND license.