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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Upconversion of IR Radiation in a KGd(WO{sub 4}){sub 2} Crystal on Erbium and Thulium Ions in Trace Concentrations: Change of Excitation Schemes and Energy Transfer Through the Crystal Lattice

Data on the observation of simultaneous upconversion on trace erbium and thulium ions in a KGd(WO{sub 4}){sub 2} crystal excited by IR radiation with the wavelength near 806 nm are presented. The change of excitation schemes with an increase in pumping level and participation of the crystal matrix in the energy transfer from erbium to thulium ions are discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Optical Properties of Thulium-Modified Silver Nanoparticles

We have prepared silver nanoparticles in thulium-modified colloidal solutions by “green” synthesis and investigated the optical properties of the resultant mixed solutions. The thulium ions have been shown to influence the properties of the colloidal silver nanoparticles. Thulium has a strong advantageous effect on the plasmon resonance of the silver nanoparticles, whereas the components of peppermint reduce the effect. The silver nanoparticles reduce the thulium ion photoluminescence intensity.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2024

Optical characterizations of densely doped Tm 3+ :KYW crystals at low temperatures

Abstract We investigate the optical lifetime, decay characteristics, spectral linewidth and energy level properties of thulium ions doped in a KY(WO 4 ) 2 crystal at 4 K temperature. High doping concentration of thulium ions with inhomogeneous broadening allow us to study nonradiative behaviors, instantaneous spectral diffusion, and spectral power broadening in this solid-state material. The theoretical consideration of ion–ion interactions is shown to accurately characterize the absorption, decay and other spectral behaviors of Tm 3 + ions. We observe more than ten-fold reduction in the decay time of 3 H 4 state and about three-fold reduction in the spectral-hole lifetime as we approach the center of the inhomogeneous broadening, corresponding to higher optical densities.

Lei, Yisheng (ORCID:0009000410141189)↗
DOE OSTI2018

Planar waveguide structures based on SrF{sub 2}: Ho, Er, Tm. Dependence of the refractive index on the dopant concentration

Refractive indices of SrF{sub 2} crystals doped with holmium, erbium, and thulium ions are measured. These crystals are used as active laser media, in particular, as materials for planar waveguides. The presence of active ions in these crystals may create a difference between the refractive indices of the cladding and the doped core of a planar waveguide. At dopant concentration to 4 %, the difference Δn between the refractive indices of the doped core and undoped reflective layer can reach 0.007.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Experimental study of a VBG-based Tm : YLF slab laser at different output coupler parameters

The performance of a Tm : YLF slab laser is studied at different output coupler parameters. Use is made of a 20-mm-long a-cut slab crystal doped with 2.5 at. % thulium ions. With a volume Bragg grating and a Fabry – Perot etalon, the selected output wavelength of this Tm : YLF slab laser is 1908 nm. For the optimised output coupler with a transmission of 20% and a radius of curvature of 300 mm, the output power exceeds 74.1 W and the slope efficiency with respect to the absorbed pump power reaches 48.4%. In addition, the beam quality of the Tm : YLF slab laser is improved. (lasers)

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2022

Size-Dependent Photon Avalanching in Tm 3+ Doped LiYF 4 Nano, Micro, and Bulk Crystals

Photon avalanche (PA) is a highly nonlinear mode of upconversion that is characterized by 100–1000-fold increase in luminescence intensity upon minute increments of pumping power. The practical realization of numerous possible nano-bio-technology applications utilizing the PA phenomenon will require information on its susceptibility to the material volume and surface. In this report these parameters are investigated via experimental and theoretical PA. The two-color, highly nonlinear PA emission at 475 and 800 nm is clearly observed in bulk single crystal, individual microcrystals, and ensembles of colloidal core and core–shell nanoparticles of LiYF 4 host doped with either 3 or 8% of thulium ions. The properties of PA emission, such as PA nonlinearity, PA gain, PA intensity, and luminescence kinetics in these materials show dependence on crystal volume and surface quenching. Theoretical simulations provide understanding of key physical processes that influence PA performance. Moreover, photon avalanche single beam super-resolution imaging is realized for the first time in 3% Tm 3+ doped LiYF 4 core–shell nanoparticles. The obtained insights and predictions form a solid background for further development and applications of new optimized PA materials.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Optical and photoluminensce properties of Eu{sup 2+}-activated strontium magnesium silicate phosphors using different rare earth co-activators

Nanostructured powders of Sr{sub 1.96}MgSi{sub 2}O{sub 7}:Eu{sub 0.01}{sup 2+}, R{sub 0.01}{sup 3+} (R{sup 3+ }= Er{sup 3+}, Tm{sup 3+} and Tb{sup 3+}) have been fabricated via urea combustion technique. XRD results implied that tetragonal Sr{sub 2}MgSi{sub 2}O{sub 7} was the major phase whereas monoclinic Sr{sub 2}SiO{sub 4} and SrSiO{sub 3} were the minor phases. Meanwhile, field emission SEM textures showed the hollow spherical network-like shape structures filled with fused interconnections for the Sr{sub 1.96}MgSi{sub 2}O{sub 7}:Eu{sub 0.01}{sup 2+} sample. It has been recognized that the replacement of Sr{sup 2+} with co-dopant R{sup 3+} ions e.g. Er{sup 3+}, Tm{sup 3+} and Tb{sup 3+} considerably help obtaining homogeneous structure as well. The values of band gap energy and calculated refractive index were ultimately dependant on the ionic radius of R{sup 3+} co-doping ion. It has been suggested that the divalent activator ion (Eu{sup 2+}) was responsible for the number of PL emission spectra, while the trivalent co-activator ions (R{sup 3+}) were the key reasons for variations in the broadening and intensity of PL emission spectra.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2011

Vacuum ultraviolet and near-infrared excited luminescence properties of Ca{sub 3}(PO{sub 4}){sub 2}:RE{sup 3+}, Na{sup +} (RE=Tb, Yb, Er, Tm, and Ho)

Tb{sup 3+}, Yb{sup 3+}, Tm{sup 3+}, Er{sup 3+}, and Ho{sup 3+} doped Ca{sub 3}(PO{sub 4}){sub 2} were synthesized by solid-state reaction, and their luminescence properties were studied by spectra techniques. Tb{sup 3+}-doped samples can exhibit intense green emission under VUV excitation, and the brightness for the optimal Tb{sup 3+} content is comparable with that of the commercial Zn{sub 2}SiO{sub 4}:Mn{sup 2+} green phosphor. Under near-infrared laser excitation, the upconversion luminescence spectra of Yb{sup 3+}, Tm{sup 3+}, Er{sup 3+}, and Ho{sup 3+} doped samples demonstrate that the red, green, and blue tricolored fluorescence could be obtained by codoping Yb{sup 3+}-Ho{sup 3+}, Yb{sup 3+}-Er{sup 3+}, and Yb{sup 3+}-Tm{sup 3+} in Ca{sub 3}(PO{sub 4}){sub 2}, respectively. Good white upconversion emission with CIE chromaticity coordinates (0.358, 0.362) is achieved by quadri-doping Yb{sup 3+}-Tm{sup 3+}-Er{sup 3+}-Ho{sup 3+} in Ca{sub 3}(PO{sub 4}){sub 2}, in which the cross-relaxation process between Er{sup 3+} and Tm{sup 3+}, producing the {sup 1}D{sub 2}-{sup 3}F{sub 4} transition of Tm{sup 3+}, is found. The upconversion mechanisms are elucidated through the laser power dependence of the upconverted emissions and the energy level diagrams. - Graphical abstract: The CPO:0.25Tb{sup 3+}, 0.25Na{sup +} exhibits a comparable brightness to the commercial Zn{sub 2}SiO{sub 4}:Mn{sup 2+} upon 147 nm excitation. Good white light color is achieved in CPO:Yb{sup 3+}-Tm{sup 3+}-Er{sup 3+}-Ho{sup 3+} under 980 nm excitation. Highlights: > Ca{sub 3}(PO{sub 4}){sub 2}:Tb{sup 3+},Na{sup +} exhibits a comparable brightness with commercial Zn{sub 2}SiO{sub 4}:Mn{sup 2+}. > Red, green and blue colors are achieved in Yb{sup 3+}, Ho{sup 3+}, Er{sup 3+}, Tm{sup 3+} doped Ca{sub 3}(PO{sub 4}){sub 2}. > Good white emission is obtained in Yb{sup 3+}-Ho{sup 3+}-Er{sup 3+}-Tm{sup 3+} quadri-doped Ca{sub 3}(PO{sub 4}){sub 2}. > Ca{sub 3}(PO{sub 4}){sub 2}:Tb{sup 3+}, Yb{sup 3+}, Ho{sup 3+}, Er{sup 3+}, Tm{sup 3+} could be potential phosphors.

36 MATERIALS SCIENCE↗
DOE OSTI2012

Photoluminescence properties of rare earths (Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+} and Tm{sup 3+}) activated NaInW{sub 2}O{sub 8} wolframite host lattice

The photoluminescence (PL) studies on NaIn{sub 1-x}RE{sub x}W{sub 2}O{sub 8}, with RE=Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+} and Tm{sup 3+} phases have shown that the relative contribution of the host lattice and of the intra-f-f emission of the activators to the PL varies with the nature of the rare earth cation. In the case of Dy{sup 3+} and Tm{sup 3+} activators, with yellow and blue emission, respectively, the energy transfer from host to the activator plays a major role. In contrast for Eu{sup 3+}, with intense red emission, the host absorption is less pronounced and the intra-f-f transitions of the Eu{sup 3+} ions play a major role, whereas for Tb{sup 3+} intra-f-f transitions are only observed, giving rise to green emission. - Graphical abstract: NaInW{sub 2}O{sub 8} double tungstate doped with Eu{sup 3+}, Dy{sup 3+}, Tb{sup 3+}and Tm{sup 3+} shows characteristic emission of intense red for Eu{sup 3+}, yellow for Dy{sup 3+}, green for Tb{sup 3+} and blue for Tm{sup 3+}. Highlights: Black-Right-Pointing-Pointer Characteristic emissions of rare earths (Eu{sup 3+}, Tb{sup 3+}, Dy{sup 3+} and Tm{sup 3+}) are observed NaInW{sub 2}O{sub 8} wolframite. Black-Right-Pointing-Pointer Energy transfer from host to the activators (Eu{sup 3+} Dy{sup 3+} Tm{sup 3+} is observed. Black-Right-Pointing-Pointer PL properties of rare earth ions depend on minor structural variations in the host lattice.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2013

Preparation and spectroscopic properties of rare-earth (RE) (RE = Sm, Eu, Tb, Dy, Tm)-activated K{sub 2}LnZr(PO{sub 4}){sub 3} (Ln = Y, La, Gd and Lu) phosphate in vacuum ultraviolet region

Graphical abstract: Display Omitted Highlights: ► We report the VUV spectroscopic properties of rare-earth ions in K{sub 2}LnZr(PO{sub 4}){sub 3}. ► The O{sup 2−}-Eu{sup 3+} charge transfer bands at about 220 nm have been observed. ► The 4f–5d spin-allowed and spin-forbidden transitions of Tb{sup 3+} have been observed. ► There is energy transfer between the host and rare-earth activators. -- Abstract: Rare earth (RE = Sm, Eu, Tb, Dy and Tm)-activated K{sub 2}LnZr(PO{sub 4}){sub 3} (Ln = Y, La, Gd and Lu) have been synthesized by solid-state reaction method, and their vacuum ultraviolet (VUV) excitation luminescent characteristics have been investigated. The band in the wavelength range of 130–157 nm and the other one range from 155 to 216 nm with the maximum at about 187 nm in the VUV excitation spectra of these compounds are attributed to the host lattice absorption and O–Zr charge transfer transition, respectively. The charge transfer bands (CTB) of O{sup 2−}-Sm{sup 3+}, O{sup 2−}-Dy{sup 3+} and O{sup 2−}-Tm{sup 3+}, in Sm{sup 3+}, Dy{sup 3+} and Tm{sup 3+}-activated samples, have not been obviously observed probably because the 2p electrons of oxygen are tightly bound to the zirconium ion in the host lattice. For Eu{sup 3+}-activated samples, the relatively weak O{sup 2−}-Eu{sup 3+} CTB at about 220 nm is observed. And for Tb{sup 3+}-activated samples, the bands at 223 and 258 nm are related to the 4f-5d spin-allowed and spin-forbidden transitions of Tb{sup 3+}, respectively. It is observed that there is energy transfer between the host lattice and the luminescent activators (e.g. Eu{sup 3+}, Tb{sup 3+}). From the standpoint of luminescent efficiency, color purity and chemical stability, K{sub 2}GdZr(PO{sub 4}){sub 3}:Sm{sup 3+}, Eu{sup 3+}, Tb{sup 3+} are attractive candidates for novel yellow, red, green-emitting PDP phosphors.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Novel kinds of down/up-conversion luminescent rare earth doped fluoride BaMgF{sub 4}: RE{sup 3+} microcrystals

Graphical abstract: We achieve the liquid phase chemical synthesis of rare earth fluoride system BaMgF4: RE{sup 3+} microphosphors, which realize down/up-conversion luminescence. - Highlights: • Doped BaMgF{sub 4} microphosphors are firstly prepared by hydrothermal process. • Doped BaMgF{sub 4} nanosheets are firstly prepared by high temperature solution reaction. • The down-conversion luminescence is realized in the rare earth doped BaMgF{sub 4}. • The upconversion luminescence is realized in the rare earth doped BaMgF{sub 4}. - Abstract: In this paper, we realize the liquid-phase chemical synthesis of high-quality orthorhombic polycrystalline BaMgF{sub 4}: RE{sup 3+} (RE = Eu, Tb, Sm, Dy, Yb–Er/Tm) compounds with hydrothermal and high-temperature solution methods, respectively. The products from hydrothermal technology show the micrometer size while the products from hydrothermal technology present nanosheet morphology. The rare earth ions doped BaMgF{sub 4} from hydrothermal synthesis are discussed in details, which can realize the downconversion luminescence for doped Eu{sup 3+} or Tb{sup 3+} and upconversion luminescence for Yb{sup 3+}/Er{sup 3+} (Tm{sup 3+}), respectively. To our knowledge, the hydrothermal or high temperature solution synthesis and photoluminescence (Eu{sup 3+}, Tb{sup 3+} or Yb{sup 3+}/Er{sup 3+}(Tm{sup 3+})) of these fluoride systems are firstly reported.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Wide band long persistent luminescence of Ca3Ga2Ge3O12: Tb3+, Tm3+ phosphor with synergistic effect of different traps

Highlights: • Novel color-tunable persistent luminescence Ca{sub 3}Ga{sub 2}Ge{sub 3}O{sub 12}: Tb{sup 3+}, Tm{sup 3+} phosphors were synthesized by a high-temperature solid-state reaction. • Better persistent luminescence properties according to the synergistic effect of different traps. • The persistent luminescence properties at high-temperature was studied. - Abstract: The as-prepared Ca{sub 3-x-y}Ga{sub 2}Ge{sub 3}O{sub 12} (CGGO): xTb{sup 3+}, yTm{sup 3+} phosphors exhibit a color-tunable long persistent luminescence (LPL) after the near-ultraviolet irradiation. Our results indicate that the shallow traps act as not only the trapping centers but also the bridge that contributes to the release of the carriers from deeper traps at room-temperature (RT), improving the LPL properties significantly. Moreover, the CGGO: xTb{sup 3+}, yTm{sup 3+} phosphors exhibit an advantageous LPL performance at high-temperature because of the existence of deeper defect states.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2014

Supercontinuum generation and lasing in thulium doped tellurite microstructured fibers

We report supercontinuum (SC) generation in Tm{sup 3+} doped tellurite microstructured fibers (TMFs) pumped by a 1.56 μm femtosecond fiber laser. In comparison with SC generation in undoped TMFs, the SC spectral bandwidth and the spectral intensity in the wavelength region of >1.9 μm are evidently enlarged in Tm{sup 3+} doped TMFs owing to the contribution of the combination of linear gain of Tm{sup 3+} and the nonlinear optical effects to spectral broadening. Furthermore, a transition from SC generation to 1.887 μm lasing (Tm{sup 3+}: {sup 3}F{sub 4}→{sup 3}H{sub 6} transition) is observed in Tm{sup 3+} doped TMFs by varying the pulse width of the pump laser from 0.29 to 3.47 ps, which gives the evidence of the above spectral broadening mechanism. This is the first observation of the transition from SC generation to lasing, to the best of our knowledge.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2015

Ferromagnetic and paramagnetic magnetization of implanted GaN:Ho,Tb,Sm,Tm films

The SQUID magnetic measurements were performed on the GaN films prepared by metal-organic vapour phase epitaxy and implanted by Tb{sup 3+}, Tm{sup 3+}, Sm{sup 3+}, and Ho{sup 3+} ions. The sapphire substrate was checked by the electron paramagnetic resonance method which showed a content of Cr{sup 3+} and Fe{sup 3+} impurities. The samples 5 × 5 mm{sup 2} were positioned in the classical straws and within an estimated accuracy of 10{sup −6 }emu, no ferromagnetic moment was detected in the temperature region of 2–300 K. The paramagnetic magnetization was studied for parallel and perpendicular orientation. In the case of GaN:Tb sample, at T = 2 K, a pronounced anisotropy with the easy axis perpendicular to the film was observed which can be explained by the lowest quasi-doublet state of the non-Kramers Tb{sup 3+} ion. The Weiss temperature deduced from the susceptibility data using the Curie-Weiss (C-W) law was found to depend substantially on the magnetic field.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2015

Synthetic and spectroscopic studies of vanadate glaserites II: Photoluminescence studies of Ln:K{sub 3}Y(VO{sub 4}){sub 2} (Ln=Eu, Er, Sm, Ho, or Tm)

Glaserite-type potassium yttrium double vanadates (K{sub 3}Y(VO{sub 4}){sub 2}) doped with Eu{sup 3+}, Er{sup 3+}, Sm{sup 3+}, Ho{sup 3+}, or Tm{sup 3+} have been synthesized by solid state reactions at 1000 °C for 48 h and their photoluminescence properties investigated. Efficient energy transfer from the vanadate group to the rare earth ion has been established by photoluminescence investigation. Ultraviolet excitation into the metal to ligand charge transfer band of the vanadate groups results in orange-red, blue and green emissions from Eu{sup 3+} (592 nm), Sm{sup 3+} (602 nm), Tm{sup 3+} (475 nm), Er{sup 3+} (553 nm), and Ho{sup 3+} (541–551 nm) dopant ions. The emission intensities of the lanthanide-doped K{sub 3}Y(VO{sub 4}){sub 2} powders were studied as a function of dopant ion concentrations. Over the concentration ranges studied, no emission quenching was observed for Eu{sup 3+} or Ho{sup 3+} dopants, while Er{sup 3+}, Sm{sup 3+} and Tm{sup 3+} dopants did exhibit such effects for dopant ion concentrations greater than 5%, probably due to cross relaxation processes. - Graphical abstract: Synthesis and photoluminescence in vanadate glaserites. - Highlights: • K{sub 3}Y(VO{sub 4}){sub 2} doped with Eu, Er, Tm, Sm, or Ho were synthesized via solid-state reactions. • Photoluminescence properties are investigated. • The lanthanide doped K{sub 3}Y(VO{sub 4}){sub 2} compounds revealed efficient energy transfer from the vanadate group to the rare earth ions. • The presented compounds are promising materials for light display systems, lasers, and optoelectronic devices.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

∼2 μm emission properties and non-radiative processes of Tm{sup 3+} in germanate glass

In this paper, 80GeO{sub 2}-8Ga{sub 2}O{sub 3}-10BaO-2Nb{sub 2}O{sub 5}-6PbO (in mol%) glass samples with different Tm{sub 2}O{sub 3} concentrations (0, 0.5, 0.75, 1, 1.25, and 1.5 mol. %) were prepared by traditional melt-quenching method. According to the measurement of thermal properties of the host glass, the glass transition temperature is 596.7 °C and no crystallization peak is observed. Judd–Ofelt parameters Ω{sub t} (t = 2, 4, 6) and fluorescent lifetimes were obtained by Judd-Ofelt theory. The similar values of Judd–Ofelt parameters and the full-width at half-maximums of ∼1800 nm indicate the local environment of Tm{sup 3+} changes little with increment of Tm{sub 2}O{sub 3} concentrations. Maximum stimulated emission cross-section of ∼1800 nm is 6.22 × 10{sup −21} cm{sup 2} as calculated by Fuchtbauer–Ladenburg formula. Energy migration among Tm{sup 3+} ions was analyzed by the extended overlap integral method. The non-radiative transition rates between mainly energy levels of Tm{sup 3+} were calculated. Non-radiative transition rate of {sup 3}F{sub 4} energy level caused by OH was analyzed by rate equation and deduced by fitting the fluorescence decay curve.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Effect of Configuration Interaction of Rare-Earth Ion States on the Intensity of Intermultiplet Transitions

We present the analysis of wave functions and the effect of configuration interaction on the intensity of absorption bands for Pr{sup 3+}, Tm{sup 3+}, and Er{sup 3+} ions. It is shown that due to the strong spin–orbit interaction the wave functions of rare-earth ions are multicomponent superpositions of ″pure″ {sup 2S+1}L{sub J} multiplets with different values of S and L and the same values of the angular momentum J. For this reason, the effect of configurational interaction depends not only on the energy gap up to excited configurations, but also on the presence of high-energy {sup 2S+1}L{sub J} components. The presence of such components yields a strong influence on the configuration interaction even at the deep layers. Another consequence of the multicomponent composition of the wave functions is the formation of groups of strongly interrelated states. When the configuration interaction is not fully taken into account, the error in describing the oscillator strengths is distributed among all the states of the group, and the low overall accuracy of the description is not perceived as a contradiction to the theory. To confirm the proposed assumptions, the oscillator strengths of the absorption transitions of laser materials activated by Pr{sup 3+}, Tm{sup 3+}, and Er{sup 3+} ions are described using the modified Judd–Ofelt theory.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

Long persistent and optically stimulated luminescence behaviors of calcium aluminates with different trap filling processes

Properties of long persistent luminescence (LPL) and optically stimulated luminescence (OSL) of CaAl{sub 2}O{sub 4}:Eu{sup 2+}, R{sup 3+} (R=Nd, Dy, Tm) materials were investigated. The observed phenomenon indicates that R{sup 3+} ions (R=Nd, Dy, Tm) have different effects on trap properties of CaAl{sub 2}O{sub 4}:Eu{sup 2+}. The greatly improved LPL performance was observed in Nd{sup 3+} co-doped samples, which indicates that the incorporation of Nd{sup 3+} creates suitable traps for LPL. While co-doping Tm{sup 3+} ions, the intensity of high temperature of thermoluminescence band in CaAl{sub 2}O{sub 4}:Eu{sup 2+} phosphors is enhanced for the formation of the most suitable traps which benefits the intense and stable OSL. These results suggest that the effective traps contributed to the LPL/OSL are complex, of which could be an aggregation formation with shallow and deep traps other than simple traps from co-doped R{sup 3+} ions. The mechanism presented in the end potentially provides explanations of why the OSL of CaAl{sub 2}O{sub 4}:Eu{sup 2+}, R{sup 3+} exhibits different read-in/read-out performance as well. - Graphical abstract: OSL emission spectra of Ca{sub 0.995}Al{sub 2}O{sub 4}:0.0025Eu{sup 2+}, 0.0025R{sup 3+} (R=Nd, Dy, Tm) taken under varying stimulation time (0, 25, 50, 75, 100 s). Inset: Blue emission pictures under varying stimulation time. - Highlights: • The LPL and OSL properties of CaAl{sub 2}O{sub 4}:Eu{sup 2+}, R{sup 3+} were investigated. • An alternative approach to control the trap depth of CaAl{sub 2}O{sub 4}:Eu{sup 2+} phosphor was proposed. • A new oxide ETM phosphor exhibiting intense and stable OSL was explored.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗