Development of NIR-Emitting Scintillators Based on Rare-Earth-Doped Garnet Crystals – Part 1

Abstract

In this paper, we report on experimental results towards the development of near-infrared (NIR)-emitting scintillators based on rare-earth-doped garnet crystals, which were obtained as a part of collaborative research with the Nuclear Power Safety Technology Research Center, Chubu Electric Power Co., Inc. A series of garnet scintillators, Y 3 Al 5 O 12 (YAG) and Y 3 Al 2 Ga 3 O 12 (YAGG) doped with rare-earth elements (Nd, Sm, Ho, Er, Tm, and Yb) at varying concentrations (0.5, 1.0, 2.0, 5.0, and 10.0 mol%), were synthesized by the floating zone method and systematically characterized for NIR-emitting scintillator applications. Among all the samples, 5% Nd-doped YAG showed the highest scintillation intensity (integration mode). By taking the spectral responsivity of the photodetector and the attenuation of optical light guide into consideration, a combination of 5% Yb-doped YAG and an InGaAs detector is expected to give the highest detectable signal. The scintillation intensity effectively depends on the photoluminescence quantum yield and energy transfer efficiency, which is effectively correlated with not the quality of the crystal but the type of rare-earth ion doped.

Radiation-induced Luminescence Properties of Tm-doped Bi4Ge3O12 Single Crystals

“…Additionally, the NIR scintillation of Tm has been reported. (31)(32)(33) For high-dose field monitoring near and inside a nuclear reactor, NIR scintillators need to detect a dose rate of 0.1 mGy/h. (21) In this study, we fabricated BGO single crystals with different concentrations of Tm, the photoluminescence (PL) and scintillation properties of which were evaluated.…”

Copper iodide semiconductor: a non-hygroscopic, bright red-emitting scintillator for X-ray and gamma-ray detection

“…Over the past few years, red and near-infrared emitting compounds have shown great potential as next-generation scintillators. For instance, rare-earth-doped garnet, 11,12) perovskite, [13][14][15] vanadate, [16][17][18][19] and other compounds 20,21) show an efficient near-infrared scintillation (800-1200 nm) and good dose response linearity with a large dynamic range for high dose monitoring applications. The near-infrared emission is owing to 4f-4f electron transitions in trivalent rare-earth ions, which is detectable by InGaAs-based detectors.…”

X-Ray Excited Luminescence Spectroscopy and Imaging with NaGdF4:Eu and Tb

“…Scintillators are luminescent materials that absorb high-energy radiation (ɤand X-ray photons, high energy ions, neutrons, or other subatomic particles) and emit UV, visible and/or NIR light [1,2]. These materials are widely used radiation detection [3] and imaging applications [4][5][6], and occasionally in external power-free light generation applications (e.g., old luminescent watches, emergency lighting and gun sites) [7]. Recently, there has been much interest in developing scintillator nanophosphors for improved X-ray luminescence imaging [8][9][10], radiation imaging [9,11,12], and as a potential light source for photochemistry and photobiology (e.g., X-ray excited optogenetics [13]).…”