Stimulated Luminescence Properties Research Articles

A review of the optically and thermally stimulated luminescence properties of aluminosilicates

This paper reviews the main literature describing models for thermoluminescence (TL), optically stimulated luminescence (OSL) and radiophotoluminescence (RPL) in aluminosilicate materials, namely natural feldspar minerals and synthetic glasses. The work examines the different models proposed to explain the various luminescence phenomena and compares them with each other. The models include thermally and optically stimulated excited-state tunneling, band-tail state hopping, and ionization and transportation through the band-tail states and/or the conduction band. Temperature and stimulation wavelength are critical parameters, with one model or another dominating over different temperature and/or wavelength ranges. Some recommendations for future research are noted.

Photoluminescence and thermally stimulated luminescence properties of Sr3Y(PO4)3 single crystals doped with Dy

Sr3Y(PO4)3 (SYPO) is recognized as a highly promising material for dosimetry applications, owing to its dosimetric properties. In this work, we synthesized the SYPO single crystals doped with 0.1, 0.5, 1, and 5% Dy using the floating zone furnace to evaluate the photoluminescence and thermally stimulated luminescence (TSL) characteristics. All the SYPO single crystals doped with Dy exhibited emission peaks at 480, 580, 670, and 760 nm in PL and TSL spectra. These emission peaks were typical for the 4f–4f transitions of Dy3+ ions. The SYPO single crystal doped with 0.1% Dy displayed a glow peak in the TSL glow curve at 70 °C. The SYPO single crystals doped with 0.5, 1, and 5% Dy showed two glow peaks at approximately 70 and 110 °C. The SYPO single crystal doped with 0.5% Dy exhibited the highest TSL intensity with a lower detection limit of 0.1 mGy. The SYPO single crystal doped with 0.5% Dy showed a spatial resolution of 50.0 μm after X-ray irradiation of 1Gy.

Study of Thermoluminescence and Optically Stimulated Luminescence Properties of Synthesised CaB2O4 Nanoparticles Doped with Copper.

CaB2O4 nanorods doped with different concentrations of Cu were prepared by using co-precipitation method. The recorded Thermoluminescence (TL) and Optically stimulated luminescence (OSL) of CaB2O4:Cu samples for different concentrations of Cu irradiated with 6Gy of X-Ray shows that 0.05 at.wt% of Cu concentrations have higher sensitivity. The TL and OSL kinetic parameters of glow curves were evaluated using "tgcd" and conventional fitting methods. The TL glow curve of the CaB2O4:Cu have three individual glow peaks with maximum peak temperatures at 404.50, 453.04 and 484.02K respectively. The OSL glow curves of the CaB2O4:Cu nanoparticles follow non-first order kinetics which can be fitted with the sum of two first order decay curves.

DFT study of the role and possible contribution of defects to lithium metasilicate [formula omitted] luminescence

Lithium metasilicate (Li2SiO3) has recently been shown to display outstanding stimulated luminescence properties, which are governed by defects and/or impurities. Here, the possible contribution and character of native point and complex defects to stimulated luminescence of lithium metasilicate have been investigated employing calculations based on the density functional theory (DFT). Under high concentrations of acceptor defects, isolated lithium interstitials were found to be the defects with the lowest formation energy (0.41 eV) but it is shown that they cannot contribute to luminescence. On the other hand, Oi−2 are the most favorable and stable defects under high concentrations of donor defects. F-centers and oxygen peroxides were identified as first- and second-order processes of point defects, which would explain experimental observations in the literature. Bridging oxygen vacancies were shown to introduce shallow electron traps able to trap up to four electrons. On the contrary, non-bridging oxygen vacancies lead to the formation of deep color centers with the capability of trapping up to two carriers/center, which could be the final state for the radiative process of luminescence. These results provide guidance for the interpretation of experimental measurements of luminescence.

Limitations of quartz extracted from Antarctica sediments for luminescence dating

Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) properties of quartz samples extracted from soil of Fisher Island (76° 13ʹ 23.9ʺ E, 69° 23ʹ 31.9ʺ S) in Antarctica were studied. The nature of signals indicated presence of a dominant slow component in the OSL signal. The widely utilized Single Aliquot Regenerative (SAR) protocol for dose recovery was found unsuitable for this particular sample due to the dominating slow component in the OSL signal. Efforts to minimize the effect of slow component in dose recovery by adopting procedures like, bleaching with blue light, and early background subtraction were carried out. Additionally, thermally transferred OSL (TT-OSL) studies were conducted on the natural sample and dose estimation using the TT-OSL SAR protocol was carried out.

Optically stimulated luminescence properties of In-doped CsBr transparent ceramics

0.01, 0.1, 0.5, and 1% In-doped CsBr transparent ceramics were synthesized by the spark plasma sintering method. Their photoluminescence and optically stimulated luminescence (OSL) properties were evaluated. All the samples showed transparency with transmittances of 40–60%. Luminescence due to 3P1–1S0 transitions of In + appeared at 500 nm. OSL emission peaks were confirmed at 500 nm upon constant stimulation light at 630 nm. A 0.1% In-doped sample showed the highest OSL intensities in prepared samples and the dose-response relationship was linear from 0.01 to 1000 mGy. The spatial resolution of X-ray images was confirmed from 5.00 LP/mm by using OSL of a 0.1% In-doped sample.

Infrared stimulated luminescence properties of highly sensitive K2SO4:Cu phosphor

The objective of this work is to investigate the dosimetric properties of a newly developed phosphor, which is potassium sulfate doped with copper. K2SO4:Cu exhibits high sensitivity as a radiation detector in the infrared stimulated luminescence (IRSL) method. The phosphor allows for dose measurements of the order of μGy using an appropriately sensitive luminescence reader. Basic dosimetric properties were examined, including: detection limit, dose-response over a wide dose range (eight orders of magnitude), reproducibility, reusability, signal bleaching and signal stability (fading) during a long time after irradiation (up to six months). The results showed dose linearity in the range of at least 1 mGy - 10 Gy, minimum detectable dose in the order of μGy and no signal loss several days after irradiation. At longer intervals after exposure, the signal begins to fade. Due to the high sensitivity of the material, despite fading, the IRSL signal still remains at a sufficient level after several months. In addition to fading, signal regeneration was noticed in the material and preliminarily studied.

Photoluminescence and thermally stimulated luminescence properties of undoped and Tb-doped Sr3Gd(PO4)3 single crystals

Using the floating zone method, undoped and 0.5, 1, and 5% Tb-doped Sr3Gd(PO4)3 (SGPO) single crystals were synthesized. Investigations were conducted on the photoluminescence (PL) and thermally stimulated luminescence (TSL) of all the SGPO single crystals. The highest PL quantum yield was shown in the 5% Tb-doped single crystal among the synthesized SGPO single crystals. The undoped SGPO single crystal displayed an emission peak in both TSL and PL at 310 nm owing to the Gd3+ 4f–4f transition. In the Tb-doped SGPO single crystals, emission peaks in PL and TSL at 310–620 nm were caused by the 4f–4f transitions of Tb3+ in addition to Gd3+. In the TSL dose response function, the 1% Tb-doped SGPO single crystal exhibited the highest TSL intensity, and the TSL signal could be detected at least 0.01 mGy.

Thermally stimulated luminescence properties of Mn-doped MgAl2O4 translucent ceramics

MgAl2O4 translucent ceramics doped with Mn were fabricated by spark plasma sintering, and optical and dosimetric properties were evaluated. The 1% Mn-doped MgAl2O4 translucent ceramic exhibited a photoluminescence emission peak at 520 nm due to Mn2+. Thermally stimulated luminescence (TSL) glow peaks of the Mn-doped MgAl2O4 translucent ceramics were observed at around 60 and 260 °C. Moreover, the TSL intensity increased as the heating temperature rose to 490 °C. TSL spectra confirmed that Mn2+ had a role of recombination centers in the TSL process. The 0.01% Mn-doped MgAl2O4 translucent ceramic showed a proportional relationship between the TSL intensity and irradiation doses ranging from 0.1 to 1000 mGy.

Comparative Study on Optically Stimulated Luminescence Properties of BaCl2:Ce and BaCl2:Eu Transparent Ceramics

Comparative Study on Optically Stimulated Luminescence Properties of BaCl2:Ce and BaCl2:Eu Transparent Ceramics

Photoluminescence, Scintillation, and Thermally Stimulated Luminescence Properties of Eu-doped Al2O3 Single Crystals

Photoluminescence, Scintillation, and Thermally Stimulated Luminescence Properties of Eu-doped Al2O3 Single Crystals

Stimulated luminescence properties of natural alexandrite in response to X-ray irradiation

This paper reports for the first time the in-depth study of thermoluminescence (TL) and optically stimulated luminescence (OSL) of Brazilian alexandrite pellets (BeAl2O4: Cr3+) previously exposed to X-rays. Firstly, structural and composition analysis of alexandrite powder was performed to verify the quality of the samples. X-ray diffraction (XRD) pattern revealed that the sample is composed by chrysoberyl (alexandrite) and minor phases as quartz, kaolinite and phlogopite. The presence of several elements, including Cr and Fe, was also detected by X-ray fluorescence (XRF) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Alexandrite pellets exhibited an intense TL signal when previously irradiated with X-ray, showing from the deconvolution five glow peaks centered at 75, 130, 175, 250 and 300 °C. The activation energy (E) and frequency factor (s) were estimated using first-order and general-order kinetic equations. The deconvolution of the OSL curve for alexandrite fit reasonably into three components, characterized as fast, medium and slow. The results obtained showed that the OSL and TL signals of alexandrite pellets vary linearly as a function of the X-ray. The pellets have low fading at room temperature, maintaining 63% of the OSL signal after 10 days of sample storage. Overall, the results suggest that natural alexandrite has TL and OSL sensitivity to X-ray radiation, being a promising material to this radiation.

The dependence of thermoluminescence and optically stimulated luminescence properties of LiMgPO4: Tb,Sm,B on maximum heating temperatures

The dependence of thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of LiMgPO4:Tb,Sm,B samples prepared by the high-temperature solid-state method on maximum heating temperatures was investigated for the first time. The TL glow curves showed the ratio of peak 3 to peak 2 increased with the increase of maximum heating temperature. The influence of OSL on maximum heating temperatures showed that the sensitivity of OSL reached the maximum at the maximum heating temperature of 1000°C, which is 11.6 times higher than that of 800 °C. The relative standard deviation of the repeatability is less than 1.5% regardless of the maximum heating temperature. The minimum measurable dose (MMD) could be significantly improved by optimizing OSL parameters, such as maximum heating temperature and readout time. The MMD as low as 0.31 µGy has been achieved. The residual OSL is up to 92.3% after irradiation for 24 h. LiMgPO4:Tb,Sm,B is highly sensitive to the maximum heating temperature. Considering fast decay time, high OSL sensitivity, good repeatability, low MMD and little fading, it is recommended that the maximum heating temperature of LiMgPO4:Tb,Sm,B is 1000°C. LiMgPO4:Tb,Sm,B has great potential for daily personal and environmental cumulative dose monitoring.

The effect of boron co-doping on thermoluminescence and optically stimulated luminescence properties of LiMgPO4:Tb,Sm

The effect of boron co-doping on optically stimulated luminescence (OSL) and thermoluminescence (TL) properties of LiMgPO4:Tb,Sm,B prepared by solid-state reaction was studied. The structure of the prepared materials was confirmed by X-ray diffraction. The TL glow curves of samples irradiated with different doses of β rays were tested. No matter how much B is doped, the peaks at 190 or 280 °C are for a first-order kinetic glow curve. The activation energy and frequency factor remained almost unchanged with the increase of boron doping concentration, which indicated the trap centers of LiMgPO4:Tb,Sm,B were independent of boron doping concentration. The E at 190 and 280 °C are around 1.16 eV and 1.55 eV. Photo-ionization cross-section showed significant changes and the sensitivity of OSL reached a maximum for a concentration of 4 mol% with increasing of boron doping concentration. B-doping enhanced the OSL-signal with a factor 2.6 when B concentration is 4 mol%. The repeatability of the powders for OSL were also studied and the relative standard deviation was less than 1.5%. The minimal detectable dose (MDD) of LiMgPO4:Tb,Sm,B with a boron doping concentration of 4 mol% was 8.2 μGy. This material has a fast decay time, good repeatability, low MDD and has further research value.

Thermoluminescence and optically stimulated luminescence properties of NaMgF3:Dy,Eu synthesized by hydrothermal method and DFT calculations for the bandgap

This study indicates Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) radiation dosimetry characteristics for NaMgF3:Dy1%,Eu0.1% fluoroperovskite. Nanocrystalline NaMgF3:Dy1%,Eu0.1% material was synthesized by hydrothermal technique. The structure and optical properties were investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TG), derivative thermogravimetry (DTG), radioluminescence (RL) and photoluminescence (PL) techniques. The bands on RL spectrum at 365, 488 and 477 nm might be attributed to Eu,2+ Eu3+ and Dy3+ ion emissions, respectively. The experimentally obtained TL glow curve was analyzed by the computerized glow curve deconvolution (CGCD) and various heating rate (VHR) methods and the order of kinetics (b), activation energy (E), and frequency factor (s) were determined for the appeared four peaks of the TL glow curve with 2°C /s heating rate. The energy bandgaps were calculated and the dependence of bandgap on composition was reported through the Density Functional Theory (DFT) computation.

Development of In-doped RbBr Transparent Ceramics with Optically Stimulated Luminescence Properties

Development of In-doped RbBr Transparent Ceramics with Optically Stimulated Luminescence Properties

Thermoluminescence and Optically Stimulated Luminescence properties of in-vitro aged dental porcelain

Among the materials applied in dentistry, porcelain is the most predominant one, as it has been used for dental restorations for decades. Towards the Thermoluminescence (TL) investigation of dental porcelain, and its capability to act as a personal accident dosimeter, the present work further examines -through a series of measurement protocols-the physical mechanisms responsible for the isothermal TL signal of its main dosimetric TL peak. Moreover, the influence of light on the TL of the same main peak is studied by means of Optically Stimulated Luminescence (OSL) measurements, while the origin of the OSL signal is further investigated. Finally, the existence of very deep traps of the material is examined and discussed via specific protocols.

Luminescence dosimetry for evaluation of the external exposure in Metlino, upper Techa River valley, Southern Urals, Russia: Analysis of new results

Luminescence dosimetry was applied in the former settlement of Metlino, Southern Urals, Russia as part of a full-scale study to validate the Techa River Dosimetry System (TRDS) 2016 for the upper Techa River region. The village, which was evacuated in 1956, was located 7 km downstream of the release point of liquid radioactive waste by the Mayak plutonium facility. Several brick samples were taken from north-eastern and south-eastern walls of the granary, facing the former Techa river shoreline and floodplain. Samples were all taken at the same height and measured at different depths into the brick. For the majority of brick samples, good Optically Stimulated Luminescence properties of the quartz grains were observed. In some cases, however, strong levels of sensitization and/or signal recuperation were encountered which necessitated adjustment in the measurement protocols. Anthropogenic doses in bricks varied from 1.5 to 6.6 Gy and the horizontal profiles along both walls showed significant variation, which is explained on a qualitative basis. A dose depth profile is observed for selected samples, which is different from the dose depth profile measured and simulated for samples from the north-western wall of the granary in previous studies. This is qualitatively explained by the differences in source configuration.

Thermally stimulated luminescence properties of transparent ceramics for personal dosimetry

Transparent ceramics have attracted attention as a new optical material that can replace glasses and single crystals. In this study, we investigated the application of transparent ceramics as dosimeter materials. Specifically, thermally stimulated luminescence (TSL) properties of MgO, Al2O3, and CaF2: Mn transparent ceramics were evaluated in comparison with those of single crystals and opaque ceramics. As a result, transparent ceramics of three chemical compositions exhibited the highest TSL intensity.

Thermally stimulated luminescence properties of MgTa2O6 prepared by solid-state chemical reaction

Persistent luminescent (PLUM) materials have been developed for a variety of applications in road marking, toys decoration, safety and bio-imaging. Such materials are set to answer the need for energy conservation. In this work, Magnesium Tantalate (MgTa2O6) compound was synthesized by a conventional solid-state chemical reaction route at 800 °C for 8 h, after ball milling the mixed precursors. The MgTa2O6 compound was confirmed with only minor impurities of Ta2O5, as identified by X-ray diffraction (XRD). The scanning electron microscopy (SEM) images of MgTa2O6 showed a surface morphology with different shapes and sizes, which are bound to each other. The energy band gap of the material was approximated to 4.34 eV using the Kubelka-Munk relation. The photoluminescence (PL) spectrum displayed a broad emission between 360 and 780 nm, when the sample was excited with a 295 nm beam, as observed from the photoluminescence excitation (PLE) spectrum. Upon investigating the thermoluminescence (TL) properties of the compound, the glow curves revealed the presence of at least three prominent electron trapping centres at ∼108, ∼258, and ∼315 °C. The competition between electron trapping centres, pre-heating effects, stability of the electron trapping centres and TL fading were examined. In addition, the depth of the electron trapping centres was determined. From the TL analysis, the prominent electron trapping centres were approximated to 0.75 ± 0.04 eV, 1.28 ± 0.07 and 1.55 ± 0.02 eV. Additionally, from the stable electron trapping centres and TL signal fading study, results indicated that MgTa2O6 is a promising material for energy storage applications.