Optical and scintillation properties of Nd differently doped YLiF₄ from VUV to NIR wavelengths

Nd 0.1, 0.5, 1, and 3 mol% doped YLiF₄ crystalline scintillators were prepared by Tokuyama Corp. and their optical and scintillation properties from vacuum ultraviolet (VUV) to near infrared (NIR) wavelengths were investigated. 4f-5d absorption bands appeared in VUV and several absorption bands due to 4f-4f transition were observed in visible-NIR wavelengths. Nd³⁺ 5d-4f emission was observed around 180 nm under 160 nm excitation and intense line due to ⁴F_3/2 → ⁴I_11/2 at 1064 nm appeared under 500 nm excitation. In X-ray induced radioluminescence, both VUV and NIR emissions were observed. Scintillation decay times of VUV emission was 40-80 ns while that of 4f-4f ones at visible wavelength were around 12-15 μs. When ²⁵²Cf neutron was irradiated, VUV scintillation light yield resulted around 90 ph/n.