Ce³⁺ doped glass for radiation detection material

Wantana, N.,Kaewnuam, E.,Chanthima, N.,Kaewjaeng, S.,Kim, H.J.,Kaewkhao, J. Elsevier 2018 CERAMICS INTERNATIONAL Vol.44 No.suppl1

<P><B>Abstract</B></P> <P>The Ce<SUP>3+</SUP> doped sodium-gadolinium-aluminum-phosphate glasses, with 20Na<SUB>2</SUB>O− 10Gd<SUB>2</SUB>O<SUB>3</SUB> − 10Al<SUB>2</SUB>O<SUB>3</SUB> − (60-x)P<SUB>2</SUB>O<SUB>5</SUB> − xCeF<SUB>3</SUB> (where x = 0.00, 0.10, 0.50, 1.50, 2.00 and 3.00 mol%) composition, have been measured and analyzed. The prepared glasses were studied various properties such as physical, optical, luminescence and scintillation. The densities of glasses were found to increase with the concentration of CeF<SUB>3</SUB> while molar volumes decreased. The value of absorption edge is shifted from 313 nm of host glass to longer wavelength with CeF<SUB>3</SUB> doping. The indirect and direct band gap decreased with increasing CeF<SUB>3</SUB> content which corresponded to the molar volume reduction representing the enhancement of non-bridging oxygen (NBO) number in glass network. Photoluminescence spectra showed the strong emission bands centered between 325 and 347 nm under Ce<SUP>3+</SUP> directly excitation and Gd<SUP>3+</SUP> excitation. The optimum concentrations of CeF<SUB>3</SUB> concentration in this glass is 2.00 mol% as it resulted the maximum emission intensity. The strongest emission band of x-ray induced optical luminescence is around 375 nm. The integrated scintillation efficiency of 2.0 mol% CeF<SUB>3</SUB> doped glass was 9.6% compared with bismuth germanium oxide (BGO) crystal. The most dominant decay times of 2.0 mol% doped glass was fast as 26.8 ns that performed the rapid response with coming excitation energy. In this work, our developed glasses performed the strong and fast luminescence signal which can be applied as the scintillation material in radiation detector.</P>

Luminescence Properties of Dy3+ doped Lanthanum-Calcium-Silicaborate Glass Scintillator

박정민,하대훈,S.W. Lee,N. Chanthima,Y. Ruangtaweep,J. Kaewkhao 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.6

In this research Dy3+-doped lanthanum-calcium-silicaborate glass scintillators, with the formula 25La2O3 : 10CaO : 10SiO2 : (55-x)B2O3 : xDy2O3, were fabricated by using the melt-quenching technique. For the Dy3+ doping concentrations from 0.05 mol% to 0.5 mol% studied the luminescence properties of the Dy3+-doped glass scintillators with various radiation sources, such as X-ray, photo-, laser, and proton. To understand the absorption state, we measured the transmittance spectrum. Furthermore, X-ray, photo- and proton-induced emission spectra were measured to study the transition states of Dy3+-doped glass scintillators. The laser-induced emission spectra were measured at low temperatures in the range from 10 K to 300 K.

Up- and Downconversion Luminescence Properties of Nd^<b>3+</b>Ions Doped in Bi_<b>2</b>O_<b>3</b>-BaO-B_<b>2</b>O_<b>3</b>Glass System

Ruamnikhom, R.,Limsuwan, P.,Horprathum, M.,Chanthima, N.,Kim, H. J.,Ruengsri, S.,Kaewkhao, J. Hindawi Limited 2014 Advances In Materials Science And Engineering Vol.2014 No.-

<P>Physical, optical, and luminescence properties of Nd<SUP>3+</SUP>ions in bismuth barium borate glass system were studied. The glasses prepared by a melt quenching method were doped at various Nd2O3concentrations in compositions (40-<I>x</I>)B2O3 : 40Bi2O3 : 20BaO : <I>x</I>Nd2O3(where<I>x</I>= 0.00, 0.50, 1.00, 1.50, 2.00, and 2.50 in mol%). Luminescence properties of the glasses were studied under two excitations of 585 and 750 nm for downconversion. From both excitations, the results show emission bands in NIR region corresponding to the transitions between<SUP>4</SUP>F3/2 → <SUP>4</SUP>I9/2(900 nm),<SUP>4</SUP>F3/2 → <SUP>4</SUP>I11/2(1,060 nm), and<SUP>4</SUP>F3/2 →<SUP> 4</SUP>I13/2(1,345 nm). The luminescence intensity obtained with 585 nm excitation was stronger than 750 nm, with the strongest NIR emission at 1,060 nm. The upconversion emission spectrum exhibits strong fluorescence bands in the UV region at 394 nm ( <TEX>$ \lambda _{\text{ex}}=591$</TEX> nm). The processes are associated with excited state absorption (ESA) from<SUP>4</SUP>F3/2level to<SUP>4</SUP>D3/2level and it is the radiative decay from the<SUP>4</SUP>D3/2to ground levels (<SUP>4</SUP>D3/2 → <SUP>4</SUP>I13/2) which are responsible for the emission at 394 nm.</P>

Physical, optical and luminescence properties of B₂O₃-SiO₂-Y₂O₃-CaO glasses with Sm³⁺ions for visible laser applications

Karki, Sujita,Kesavulu, C.R.,Kim, H.J.,Kaewkhao, J.,Chanthima, N.,Ruangtaweep, Y. Elsevier 2018 Journal of luminescence Vol.197 No.-

<P><B>Abstract</B></P> <P>Silicoborate glasses with composition of (BSYCaSm:(55-x)B<SUB>2</SUB>O<SUB>3</SUB>+ 10SiO<SUB>2</SUB> +25Y<SUB>2</SUB>O<SUB>3</SUB> +10CaO + xSm<SUB>2</SUB>O<SUB>3</SUB>), (where, x= 0.05, 0.10, 0.20, 0.25, 0.30, 0.40, 0.50, mol%) have been synthesized by using the well-known melt quenching technique. The present work deals with physical, optical, photoluminescence, X-ray luminescence and decay time studies of silicoborate glasses. Judd-Ofelt (JO) intensity parameters (Ω<SUB>2,</SUB> Ω<SUB>4</SUB> and Ω<SUB>6</SUB>) and radiative properties for the important luminescent level of Sm<SUP>3+</SUP> ions were derived by using the absorption spectrum of 0.3mol% Sm<SUB>2</SUB>O<SUB>3</SUB> doped glass. The luminescence spectra in the visible region was obtained due to <SUP>4</SUP>G<SUB>5/2</SUB> → <SUP>6</SUP>H<SUB>J</SUB> (5/2, 7/2, 9/2 and 11/2) transition of Sm<SUP>3+</SUP> ion under 401nm excitation. The decay profile for the <SUP>4</SUP>G<SUB>5/2</SUB> level of Sm<SUP>3+</SUP> ions was analyzed and found that for lower concentration (≤ 0.20mol%) it is single exponential in nature whereas for higher concentration (≥ 0.25mol%), it turns in to non-exponential due to the transfer of energy between donor (excited state Sm<SUP>3+</SUP>ion) and acceptor (ground state Sm<SUP>3+</SUP> ion). As the concentration of Sm<SUP>3+</SUP> ions increases the decay time of <SUP>4</SUP>G<SUB>5/2</SUB> state decreases. The well-known Inokuti-Hirayama (IH) model was used for fitting the non-exponential decay curves where S = 6 indicates that energy transfer process is of dipole-dipole type. Hence, in the present work, intense transition of <SUP>4</SUP>G<SUB>5/2</SUB> → <SUP>6</SUP>H<SUB>7/2</SUB> (601nm) is found to be suitable for reddish-orange laser emission. CIE chromaticity diagram has been performed for verifying the results of fluorescence in visible laser applications at 601nm.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Optical and luminescence characteristics of Eu 3+ -doped B 2 O 3 :SiO 2 :Y 2 O 3 :CaO glasses for visible red laser and scintillation material applications

Aryal, Pabitra,Kesavulu, C.R.,Kim, H.J.,Lee, S.W.,Kang, Sang Jun,Kaewkhao, J.,Chanthima, N.,Damdee, B. Elsevier 2018 Journal of rare earths Vol.36 No.5

<P>Europium (Eu3+) doped glasses of chemical compositions (55-x)B2O3:10SiO(2):25Y(2)O(3):10CaO:xEu(2)O(3), where x denotes mol% and ranges 0 <= x <= 2.5, were synthesized by adopting conventional melt quenching technique. Physical properties like density, molar volume, polaron radius, inter-ionic distance and field strength of the glass samples were investigated to assess the impact of EU2O3. Optical and luminescence properties of the glasses were characterized with optical absorption, photoluminescence, X-ray induced emission spectra, temperature dependence emission spectra and decay times. Judd-Ofelt (JO) intensity parameters (omega(lambda)) of the glasses were evaluated based on the absorption spectrum of 0.5 mol%. JO parameters, calculated from absorption spectra with thermal corrections on oscillator strength, were used to evaluate radiative properties such as radiative transition probability (A(R)), branching ratio (beta(R)), stimulated cross section emission (sigma) and radiative lifetime (tau(R)) for D-5(0) -> F-7(J) (J = 0,1,2,3 and 4) transitions. The decay rate of D-5(0) fluorescent level for all the glass samples was single exponential. Lifetimes of the D-5(0) level were decreased with increasing concentrations of Eu(3+)ions from 0.05 mol% to 2.5 mol% which might be due to energy transfer through cross-relaxation in the glasses. The chromaticity coordinates (x, y) were similar for all BSYCaEu glasses and were located at the red region of CIE 1931 color chromaticity diagram. Hence, these results confirm that the Eu3+ doped BSYCaEu glasses could be useful for visible red lasers and glass scintillation applications. (C) 2017 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights reserved.</P>

A Study of Radioactive Contamination of <tex> $^{\text{40}}\text{Ca}^{\text{100}}\text{MoO}_{\text{4}}$</tex> Crystals for the AMoRE Experiment

Lee, J. Y.,Alenkov, V.,Ali, L.,Beyer, J.,Bibi, R.,Boiko, R. S.,Boonin, K.,Buzanov, O.,Chanthima, N.,Cheoun, M. K.,Chernyak, D. M.,Choi, J.,Choi, S.,Danevich, F. A.,Djamal, M.,Drung, D.,Enss, C.,Fleisc IEEE 2016 IEEE transactions on nuclear science Vol.63 No.2

<P>A calcium molybdate (CaMoO4) crystal scintillator, with molybdenum enriched in Mo-100 and calcium depleted in Ca-48 ((CaMoO4)-Ca-40-Mo-100), was developed by the Advanced Molybdenum based Rare process Experiment (AMoRE) collaboration to search for a neutrinoless double beta (0 nu beta beta) decay of Mo-100. We are planning to use about 10 kg of (CaMoO4)-Ca-40-Mo-100 crystals as cryogenic bolometers for the first phase of the experiment (AMoRE-I) at the Yang Yang underground laboratory (Y2L) in Korea. This experiment calls for an extremely low level of radioactive contamination in detectors, particularly by thorium, uranium, and radium decay chains. We measured scintillation properties and radioactive contamination of CaMoO4 and (CaMoO4)-Ca-40-Mo-100 crystals at the Y2L. We also estimated the acceptable level of internal radioactive background using Monte Carlo simulation for the AMoRE-I.</P>