Crystal growth and scintillation properties of Nd-doped Lu3Al5O12 single crystals

Scintillation properties of Nd-doped Lu₃Al₅O₁₂ (Nd:LuAG) single crystals grown by the micro-pulling down (μ-PD) method have been studied. The Nd concentration ranged from 0.1 to 3 mol%. The grown crystals were transparent and had a single-phase confirmed by powder XRD measurements. In transmittance spectra, they showed about 80% transmittance down to 300 nm and some weak 4f-4f absorption lines appeared. They showed broad emission peaks due to defects in the host and some sharp peaks due to Nd³⁺ 4f-4f transitions in radioluminescence spectra under ²⁴¹Am α-ray excitation. Their γ-ray-excited decay time profiles consisted of two components as 340-760 ns and 3-5 μs. Among them, Nd 0.5%:LuAG exhibited the highest light yield under ¹³⁷Cs 662 keV excitation and the absolute light yield of this sample was estimated to be 7600 ±760 photons/MeV.