Proton damage in (Y,Lu,Gd)₃(Al,Ga)₅O₁₂:Ce mixed garnet scintillators

Area of Science:

• Materials Science
• Nuclear Instrumentation
• Plasma Diagnostics

Background:

• Scintillators are crucial for nuclear instrumentation, particularly in plasma diagnostics and imaging.
• Increasing yields in fusion experiments necessitate robust scintillator materials with high radiation tolerance.
• Radiation exposure can degrade scintillating materials and affect their optical properties.

Purpose of the Study:

• To investigate the effects of radiation damage on Ce-doped mixed garnet ceramics.
• To determine the compositional range of (Y,Gd,Lu)3(Al,Ga)5O12 most resistant to radiation.
• To identify the optimal cerium dopant concentration for improved radiation tolerance in Y2LuAl5O12.

Main Methods:

• Samples of Ce-doped mixed garnet ceramics were exposed to 200 keV protons up to a fluence of 10^16 protons/cm^2.
• Diffuse Reflectance Spectroscopy (DRS) was used to characterize radiation-induced absorption.
• DRS was employed to assess the radiation tolerance of opaque, polycrystalline samples.

Main Results:

• Qualitative trends in induced absorption were observed as a function of ceramic composition.
• The study identified specific compositional ranges within (Y,Gd,Lu)3(Al,Ga)5O12 exhibiting varying radiation tolerance.
• The ideal cerium dopant concentration for Y2LuAl5O12 was determined to be between 0.60-0.75 mol.%.

Conclusions:

• Ce-doped mixed garnet ceramics show promise as radiation-tolerant scintillators for demanding applications.
• Polycrystalline ceramics offer advantages for characterization and fabrication compared to single crystals.
• Optimizing composition and dopant concentration is key to developing advanced scintillators for high-radiation environments.