Ce and Eu-doped LiSrAlF6 scintillators for neutron detectors

Abstract

Abstract Ce 1%, Eu 1%, and Eu 2%-doped LiSrAlF6 (LiSAF) single crystals were grown by the micro-pulling-down method for thermal neutron applications. The crystals were transparent, 2.0 mm in diameter and 20–40 mm in length. Neither visible inclusions nor cracks were observed. Their transmittance spectra were measured. The strong absorption lines were observed at 200, 240, and 300 nm for Ce:LiSAF due to Ce3+ 4f–5d transition. In Eu:LiSAF, 200 (4f–5d) and 300 (4f–4f) nm absorption lines were detected. The samples demonstrated strong emission peaks at 300 nm (Ce:LiSAF) and 370 nm (Eu:LiSAFs) when they were irradiated with 241Am α-rays simulating the α-particles from the 6Li(n, α) reaction. Thermal neutron responses were examined under 252Cf irradiation. The absolute light yield of Ce, Eu 1%, and Eu 2% crystals were 3400, 18000, and 30000 ph/n, respectively. Main components of the scintillation decay time of Ce, Eu 1%, and Eu 2%-doped LiSAFs were 63, 1293, and 1205 ns.