https://biblio.ugent.be/publication/685594/file/1130605.pdf

Review of Particle Physics

Phosphor-converted white light-emitting diodes (pc-WLEDs) are emerging as an indispensable solid-state light source for the next generation lighting industry and display systems due to their unique properties including but not limited to energy savings, environment-friendliness, small volume, and long persistence. Until now, major challenges in pc-WLEDs have been to achieve high luminous efficacy, high chromatic stability, brilliant color-rending properties, and price competitiveness against fluorescent lamps, which rely critically on the phosphor properties. A comprehensive understanding of the nature and limitations of phosphors and the factors dominating the general trends in pc-WLEDs is of fundamental importance for advancing technological applications. This report aims to provide the most recent advances in the synthesis and application of phosphors for pc-WLEDs with emphasis specifically on: (a) principles to tune the excitation and emission spectra of phosphors: prediction according to crystal field theory, and structural chemistry characteristics (e.g. covalence of chemical bonds, electronegativity, and polarization effects of element); (b) pc-WLEDs with phosphors excited by blue-LED chips: phosphor characteristics, structure, and activated ions (i.e. Ce 3+ and Eu 2+ ), including YAG:Ce, other garnets, non-garnets, sulfides, and (oxy)nitrides; (c) pc-WLEDs with phosphors excited by near ultraviolet LED chips: single-phased white-emitting phosphors (e.g. Eu 2+ –Mn 2+ activated phosphors), red-green-blue phosphors, energy transfer, and mechanisms involved; and (d) new clues for designing novel high-performance phosphors for pc-WLEDs based on available LED chips. Emphasis shall also be placed on the relationships among crystal structure, luminescence properties, and device performances. In addition, applications, challenges and future advances of pc-WLEDs will be discussed.

Phosphors in phosphor-converted white light-emitting diodes: Recent advances in materials, techniques and properties

A review of quartz optically stimulated luminescence characteristics and their relevance in single-aliquot regeneration dating protocols

The recent confirmation that at least some γ-ray bursts originate at cosmological distances1,2,3,4 suggests that the radiation from them could be used to probe some of the fundamental laws of physics. Here we show that γ-ray bursts will be sensitive to an energy dispersion predicted by some approaches to quantum gravity. Many of the bursts have structure on relatively rapid timescales5, which means that in principle it is possible to look for energy-dependent dispersion of the radiation, manifested in the arrival times of the photons, if several different energy bands are observed simultaneously. A simple estimate indicates that, because of their high energies and distant origin, observations of these bursts should be sensitive to a dispersion scale that is comparable to the Planck energy scale (∼1019 GeV), which is sufficient to test theories of quantum gravity. Such observations are already possible using existing γ-ray burst detectors.

/pdf/tests-of-quantum-gravity-from-observations-of-g-ray-bursts-36h2zmgj9a.pdf

Tests of quantum gravity from observations of γ-ray bursts

/pdf/review-of-particle-physics-1996-1997-jeg703df6k.pdf

Review of Particle Physics, 1996-1997

Inorganic scintillators for γ-ray detection are used in many fields from medical-diagnostic imaging to industrial measuring systems. Accordingly they face various demands with respect to e.g. response time, light yield, and energy resolution. The development of the new family of rare-earth halide scintillators LaCl3
				∶ Ce3+, LaBr3
				∶ Ce3+, and LuI3
				∶ Ce3+ is reviewed and their properties are compared to those of the established materials NaI ∶ Tl+ and Lu2SiO5
				∶ Ce3+. Extraordinary properties such as the short lifetime of 15 ns and the narrow energy resolution of 2.6% in LaBr3
				∶ 5% Ce3+, or the high light yield of 95000 photons per MeV in LuI3
				∶ 5% Ce3+ improve the performance of scintillators in existing applications and open the way to novel ones. The development of these new materials was empowered by the close interdisciplinary collaboration between scientists in the fields of inorganic chemistry, optical spectroscopy, and applied physics.

Development and characterization of highly efficient new cerium doped rare earth halide scintillator materials

Cerium doped lutetium pyrosilicate Lu2Si2O7:Ce3+ (LPS), a new inorganic scintillator, displays particularly promising performance. This material can be readily pulled from the melt. A high light output (average value: 26 300 ph MeV−1), a relatively good energy resolution (9%) and a fast decay time (38 ns) without afterglow make this new scintillator very attractive, in particular for medical imaging. Optical characterizations and scintillation properties of LPS:Ce large single crystals are presented, including timing properties and study of the scintillation yields as a function of incident energy.

https://iopscience.iop.org/article/10.1088/0953-8984/15/12/326/pdf

Scintillation properties of Lu2Si2O7:Ce3+, a fast and efficient scintillator crystal

Optical and scintillation properties of cerium-doped LaCl3, LuBr3 and LuCl3

The optical and scintillation properties of pure and Ce3+-doped Cs2LiYX6 (X = Cl, Br) are presented. X-ray-excited optical luminescence spectra, optical excitation and emission spectra, time-resolved excitation and emission spectra, scintillation pulse height spectra and scintillation decay time spectra of Ce3+-doped Cs2LiYX6 (X = Cl, Br) crystals measured from 10 to 300 K are presented. Factors influencing the scintillation mechanism and the presence of core?valence luminescence are discussed.

https://iopscience.iop.org/article/10.1088/0953-8984/14/36/307/pdf

Scintillation and spectroscopy of the pure and Ce3+-doped elpasolites: Cs2LiYX6 (X = Cl, Br)

There is a strong interest in the development of inorganic scintillators with a fast response for applications in high-energy physics, medical diagnostics and a number of other fields. One of the main lines of research concerns luminescence from the allowed 5d-4f transitions of lanthanide ions in appropriately chosen host lattices. Results are presented of research on Ce-doped scintillators.

C.W.E. van Eijk

Papers

Development and characterization of highly efficient new cerium doped rare earth halide scintillator materials

Scintillation properties of Lu2Si2O7:Ce3+, a fast and efficient scintillator crystal

Optical and scintillation properties of cerium-doped LaCl3, LuBr3 and LuCl3

Scintillation and spectroscopy of the pure and Ce3+-doped elpasolites: Cs2LiYX6 (X = Cl, Br)

Ce3+ doped inorganic scintillators