Ultra-Low Afterglow and Fast Decay LYSO Scintillation Crystal by Co-Doping of Ni and In

Abstract

Cerium-doped yttrium lutetium silicate (LYSO:Ce) scintillation crystals have significant application value in the field of radiation detection due to their excellent comprehensive scintillation performance. However, their strong afterglow and relatively long scintillation decay time (∼42 ns) severely limit their application in the field of high-repetition-rate ultrafast radiation detection. To address this challenge, we propose a multi-ion co-doping strategy to optimize afterglow and decay time of LYSO:Ce crystal. A series of Ni²⁺, In³⁺ co-doped LYSO:Ce,Ni,xIn crystals were prepared using the Czochralski (Cz) method, and the regulation mechanism of Ni²⁺ and In³⁺ co-doping on the scintillation performance of the crystal was systematically investigated. It was found that the co-doping of Ni²⁺ and In³⁺ can optimally shorten the excited-state lifetime of the luminescent center Ce in the crystal by approximately 40%, significantly suppressing the deep and shallow energy level traps in the crystal. This, in turn, significantly optimizes the afterglow level (reducing it by about 2 orders of magnitude) and reduces the scintillation decay time of the crystal (shortening it by approximately 32%). The collaborative co-doping strategy proposed in this work is expected to be extended to other scintillation materials with Ce as the luminescent center, enabling efficient regulation of afterglow and scintillation decay time.