Method for increasing luminescence uniformity and reducing afterglow of Ce-doped gadolinium-aluminum-gallium garnet structure scintillation crystal, crystal material and detector

A method for increasing luminescence uniformity and reducing afterglow of a Ce-doped gadolinium-aluminum-gallium garnet structure scintillation crystal, comprising:

• doping Sc ions with a ionic radius between Gd ion and Ga ion into the Ce-doped gadolinium-aluminum-gallium garnet structure scintillation crystal, so that the Sc ions occupy octahedral site and dodecahedral site at the same time, a chemical composition general formula of the obtained garnet structure scintillation crystal is {Gd1-x-y-pScxCeyMep}3[Al1-qGaq]5O12, Me is selected from one or more of a group consisting of Mg, Ca and Li, 0.01≤x≤0.05, 0.002≤y≤0.01, 0≤p≤0.003, 0.5≤q≤0.6;
• wherein
• the Sc ions occupying the dodecahedral site substitute Gd ions with a ionic radius between Ce ions and Sc ions, after the Sc enters the dodecahedron lattice, it makes the Ce ions enter the dodecahedron lattice more easily depending on the radius compensation effect, increasing the effective segregation coefficient of the Ce ions;
• the Sc ions occupying the octahedral site substitute the Ga ions with a ionic radius smaller than Sc ions, after entering the octahedral sites, the Sc ions increase lattice parameters, thereby facilitating the Ce ions to enter the dodecahedral sites with a larger space, and further increasing the effective segregation coefficient of the Ce ions;
• and the effective segregation coefficient of active Ce ions is increased by means of a radius compensation effect of Sc—Ce ions and adjustment of lattice parameters, thereby the luminescence uniformity of the scintillation crystal is increased and the energy resolution is optimized;
• and at the same time, the potential barrier for Gd ions entering the octahedral site is increased by Sc ion doping, thereby the probability of the Gd ions entering the octahedral site is reduced, the density of point defects in the scintillation crystal is decreased, and the afterglow intensity is reduced.