Eu concentration dependence on scintillation properties of Eu doped SrI2 single crystals grown by modified micro-pulling-down method

•We have grown several Eu concentration doped SrI2 single crystals by μ-PD Method.•All diffraction peaks were ascribed to corresponding SrI2 plane indices.•Luminescence originated from Eu2+ 5d–4f transition was observed near 435 nm.•Eu 7.5%:SrI2 crystals showed maximum light-yield and minimum energy resolution.

Eu doped SrI2 (Eu:SrI2) single crystals with various Eu contents were grown by a modified micro-pulling-down (μ-PD) method and effects of Eu concentration on scintillation properties were investigated. Eu 1%, 5%, 7.5%, 10% and 15%:SrI2 single crystals were obtained and all as-grown crystals indicated high transparency without visible inclusion. Actual Eu contents in the grown crystals were almost same as nominal compositions. In the X-ray radioluminescence spectra, emission peaks around 435 nm were observed in all crystals. Eu7.5 mol%:SrI2 crystals indicated the highest light yield, 78,000 ph/MeV, and the smallest energy resolution, 3.7%.