Efficient Channels of Energy Transfer in High Light Yield LuI3:Ce Scintillator

AbstractThe extremely high scintillation efficiency of lutetium iodide doped by cerium is explained as a result of several factors controlling the energy transfer from the host matrix to activator, two of which are investigated in the present paper. The first one is the increase of the efficiency of energy transfer from self-trapped excitons to cerium ions in the row LuCl3-LuBr3-LuI3. The STE structure and the efficiency of STE to cerium energy transfer are verified by cluster ab initio calculations. We propose and theoretically validate the possibility of a new channel of energy transfer to excitons and directly to cerium, namely the Auger process when Lu 4f hole relaxes to the valence band hole with simultaneous creation of additional exciton or excitation of cerium. This process should be efficient in LuI3, and inefficient in LuCl3. In order to justify this channel we perform calculations of density of states using a periodic plane-wave density functional approach. The performed estimations theoretically justify the high LuI3:Ce3+ scintillator yield.

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Luminescence and Light Yield in Ce3+-Doped Y1Gd2Al5-xGaxO12 (x=2,3,4) Single Crystal Scintillators

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.709.390 ◽

2014 ◽

Vol 709 ◽

pp. 390-393 ◽

Cited By ~ 1

Author(s):

Warut Chewpraditkul ◽

Nakarin Pattanaboonmee ◽

Weerapong Chewpraditkul ◽

Kei Kamada ◽

Akira Yoshikawa ◽

...

Keyword(s):

Energy Transfer ◽

Single Crystal ◽

Crystal Field ◽

Light Yield ◽

High Light ◽

Photoluminescence Excitation ◽

Excitation Spectra ◽

High Light Yield ◽

Γ Rays ◽

Ga Content

The compositional dependences of luminescence properties and light yield were studied in Ce3+ -doped Y1Gd2Al5-xGaxO12 (x = 2, 3, 4) single crystal scintillators. The Gd3+→ Ce3+ energy transfer was evidenced by photoluminescence excitation spectra of Ce3+ emission. With increasing Ga content in the garnet host, the Ce3+ luminescence from the lowest 5d level (5d1) was blue-shifted due to the decrease in the crystal field splitting of the 5d levels. High light yield (LY) value of ~36,000 ph/MeV was obtained for a Y1Gd2Al2Ga3O12:Ce sample under excitation with 662 keV γ-rays. The decrease of LY value was also observed with higher Ga content due to the thermal ionization from the 5d1 level to the conduction band.

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High light yield Ce3+-doped dense scintillating glasses

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2013.07.181 ◽

2013 ◽

Vol 581 ◽

pp. 801-804 ◽

Cited By ~ 39

Author(s):

Qian Wang ◽

Bin Yang ◽

Yuepin Zhang ◽

Haiping Xia ◽

Tianchi Zhao ◽

...

Keyword(s):

Light Yield ◽

High Light ◽

High Light Yield

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Development of ultra-pure NaI(Tl) detectors for the COSINE-200 experiment

The European Physical Journal C ◽

10.1140/epjc/s10052-020-8386-8 ◽

2020 ◽

Vol 80 (9) ◽

Author(s):

B. J. Park ◽

J. J. Choi ◽

J. S. Choe ◽

O. Gileva ◽

C. Ha ◽

...

Keyword(s):

Crystal Growth ◽

Direct Detection ◽

Light Yield ◽

High Light ◽

Independent Verification ◽

High Light Yield ◽

Assembly Technique ◽

Modulation Signal ◽

Standing Question ◽

Detector Assembly

AbstractThe annual modulation signal observed by the DAMA experiment is a long-standing question in the community of dark matter direct detection. This necessitates an independent verification of its existence using the same detection technique. The COSINE-100 experiment has been operating with 106 kg of low-background NaI(Tl) detectors providing interesting checks on the DAMA signal. However, due to higher backgrounds in the NaI(Tl) crystals used in COSINE-100 relative to those used for DAMA, it was difficult to reach final conclusions. Since the start of COSINE-100 data taking in 2016, we also have initiated a program to develop ultra-pure NaI(Tl) crystals for COSINE-200, the next phase of the experiment. The program includes efforts of raw powder purification, ultra-pure NaI(Tl) crystal growth, and detector assembly techniques. After extensive research and development of NaI(Tl) crystal growth, we have successfully grown a few small-size (0.61–0.78 kg) thallium-doped crystals with high radio-purity. A high light yield has been achieved by improvements of our detector assembly technique. Here we report the ultra-pure NaI(Tl) detector developments at the Institute for Basic Science, Korea. The technique developed here will be applied to the production of NaI(Tl) detectors for the COSINE-200 experiment.

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Inorganic, Organic, and Perovskite Halides with Nanotechnology for High–Light Yield X- and γ-ray Scintillators

Crystals ◽

10.3390/cryst9020088 ◽

2019 ◽

Vol 9 (2) ◽

pp. 88 ◽

Cited By ~ 31

Author(s):

Francesco Maddalena ◽

Liliana Tjahjana ◽

Aozhen Xie ◽

Arramel ◽

Shuwen Zeng ◽

...

Keyword(s):

High Energy Physics ◽

Low Cost ◽

Light Yield ◽

Fast Response ◽

High Energy ◽

High Light ◽

Scintillation Light ◽

High Light Yield ◽

Halide Perovskites ◽

Lead Halide

Trends in scintillators that are used in many applications, such as medical imaging, security, oil-logging, high energy physics and non-destructive inspections are reviewed. First, we address traditional inorganic and organic scintillators with respect of limitation in the scintillation light yields and lifetimes. The combination of high–light yield and fast response can be found in Ce 3 + , Pr 3 + and Nd 3 + lanthanide-doped scintillators while the maximum light yield conversion of 100,000 photons/MeV can be found in Eu 3 + doped SrI 2 . However, the fabrication of those lanthanide-doped scintillators is inefficient and expensive as it requires high-temperature furnaces. A self-grown single crystal using solution processes is already introduced in perovskite photovoltaic technology and it can be the key for low-cost scintillators. A novel class of materials in scintillation includes lead halide perovskites. These materials were explored decades ago due to the large X-ray absorption cross section. However, lately lead halide perovskites have become a focus of interest due to recently reported very high photoluminescence quantum yield and light yield conversion at low temperatures. In principle, 150,000–300,000 photons/MeV light yields can be proportional to the small energy bandgap of these materials, which is below 2 eV. Finally, we discuss the extraction efficiency improvements through the fabrication of the nanostructure in scintillators, which can be implemented in perovskite materials. The recent technology involving quantum dots and nanocrystals may also improve light conversion in perovskite scintillators.

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CsI:Tl+,Yb2+: ultra-high light yield scintillator with reduced afterglow

CrystEngComm ◽

10.1039/c3ce42645a ◽

2014 ◽

Vol 16 (16) ◽

pp. 3312-3317 ◽

Cited By ~ 25

Author(s):

Yuntao Wu ◽

Guohao Ren ◽

Martin Nikl ◽

Xiaofeng Chen ◽

Dongzhou Ding ◽

...

Keyword(s):

Energy Resolution ◽

Computer Tomography ◽

High Speed ◽

Light Yield ◽

High Light ◽

High Speed Imaging ◽

High Light Yield ◽

The Way

Simultaneous improvement in afterglow, light yield and energy resolution in CsI:Tl-based scintillators paves the way to its application in computer tomography and high-speed imaging.

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