Improvement of the scintillation properties of Gd₃ Ga₃ Al₂ O₁₂ :Ce,B single crystals having tailored defect structure

Abstract

A novel approach is reported to minimize various defect centers in Ce doped Gd3Ga3Al2O12 single crystals to improve the scintillation properties. The crystals of Gd3Ga3Al2O12 codoped with 0.2 at% Ce and B (GGAG:Ce,B) have been grown in air and argon ambient using the Czochralski technique. The scintillation light output of crystals grown in Ar ambient was significantly increased after annealing the crystals in air. The measured light output of 60000 ph/MeV for annealed crystals is the highest value reported among this class of materials. As a consequence, the energy resolution at 662 keV gamma‐rays from a 137Cs source was improved from 8% for the crystals grown in air to 6% for crystals grown in Ar and subsequently annealed in air. Further, the thermal quenching energy of photoluminescence (PL) emission was increased to be 470 meV for the annealed crystals. The thermoluminescence (TL) measurements suggest that the crystals grown in Ar ambient and post‐growth annealed in air may have a lesser concentration of trap centers which subsequently lead to the improvement in optical and scintillation properties leading to a superior detector performance. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)

Drastic Scintillation Yield Enhancement of YAG:Ce with Carbon Doping

“…Scintillation properties of undoped YAG were barely explored in detail due to low light yield and slow luminescence decay. Meanwhile, Ce‐doped garnets did not attract much attention until the development of extremely efficient Al/Ga‐substituted multi component garnets with the light yields of up to 58 000 phot MeV −1 . This value is near the theoretical limit considering the energy gap of these materials .…”

Organic–Inorganic Composite Films Based on Gd3Ga3Al2O12:Ce Scintillator Nanoparticles for X-ray Imaging Applications

“…The nanopowder synthesized by the coprecipitation method has been sintered at 1000 °C for 24 h and the solid-state sintered powder is sintered at 1400 °C for 24 h. The peaks are indexed and matched with the JCPDS-44-0448 database. All the samples show formation of the pure phase of GGAG:Ce. , No peaks corresponding to constituent oxides were observed. The peak width of powder prepared by coprecipitation is broader than powder synthesized by the solid state which indicated that the grain size is smaller in the case of GGAG:Ce powder synthesized by chemical technique.…”

Performance studies of compact GGAG:Ce,B thermal neutron detector coupled to Si-based photosensors

“…More details of crystal growth have been given in ref. [30]. A 5× 5× 2 mm 3 crystal was cut from an ingot crystal, polished optically and subsequently coupled to the APD and SiPM for thermal neutron detection.…”