Optical and dosimetric properties of Ti-doped (0.05, 0.1, 0.2, and 0.5%) MgAl2O4 single crystals grown by the floating zone method were investigated. All Ti-doped MgAl2O4 single crystals showed ...photoluminescence (PL) and thermally stimulated luminescence (TSL) at 470 nm. The PL decay time constant of this luminescence was approximately 6 μs, and the emission origin was ascribed to charge transfer (CT) related to Ti4+. The 0.1% Ti-doped MgAl2O4 single crystal showed the highest intensity of TSL glow peaks unlike the result of PL quantum yields (QYs). In TSL dose response functions, 0.1 and 0.2% Ti-doped MgAl2O4 single crystals showed detection limit that comparable with some commercial products.
•We have synthesized MgAl2O4 single crystals doped with Ti by floating zone method.•We have characterized the optical and dosimetric properties.•All samples showed luminescence properties due to CT related to Ti4+.
Tellurite glass (TeG) and its glass-ceramics (TeGC435 and TeGC455), with a composition of 10Eu2O3–10BaO–80TeO2, were prepared and their luminescence properties were evaluated. TeG was prepared via ...the melt quenching technique, while TeGC435 and TeGC455 were fabricated by heat treating TeG at 435 and 455 °C, respectively, for 5 h each. The Eu2Te6O15 crystal phase was formed in TeGC435 and TeGC455. Both the glass and glass-ceramics showed sharp photoluminescence and scintillation peaks, attributed to the 4f→4f transitions of Eu3+. The highest quantum yield was obtained for TeG, whereas the highest integrated scintillation intensity was obtained for TeGC455. The scintillation intensity of TeGC455 was approximately 10% of that of the Bi4Ge3O12 single crystal. Furthermore, typical decay times derived from the 4f→4f transitions were obtained for TeG, TeGC435, and TeGC455 during photoluminescence and scintillation.
TSL and OSL properties of Eu-doped LiMgAlF6 Yanagida, Takayuki; Kato, Takumi; Takebuchi, Yuma ...
Radiation measurements,
March 2020, 2020-03-00, Letnik:
132
Journal Article
Recenzirano
Different concentrations of Eu doped LiMgAlF6 samples were synthesized by the spark plasma sintering (SPS) method. In photoluminescence (PL) measurements, emission due to 5d-4f transition of Eu2+ was ...observed at 370 nm, and PL decay times resulted 1.1–2.8 μs. When we irradiated X-rays, scintillation emissions due to Eu2+ and Eu3+ were detected at 370 and 600 nm, respectively. Optically stimulated luminescence (OSL) and thermally stimulated luminescence (TSL) were also observed in Eu-doped LiMgAlF6, and especially, TSL intensity was very high.
•We prepared Eu-doped LiMgAlF6 ceramic by the spark plasma sintering method.•Photoluminescence and scintillation properties were investigated.•Optically and themelly stimulated luminescence properties were evaluated.
We synthesized the 0.1, 0.5, 1.0, and 1.5% Ce-doped mullite single crystals by the floating zone method and evaluated their photoluminescence (PL) and thermally stimulated luminescence (TSL) ...properties. The single-phase orthorhombic structure was confirmed in all the samples from powder X-ray diffraction patterns. The transmittance spectra of all the samples showed the absorption related to the 4f-5d transitions of Ce3+ ions and optical band gap of mullite. The Ce-doped mullite single crystals had the PL attributed to the 5d-4f transitions of Ce3+ ions. In TSL properties, TSL glow curves had the glow peaks at 250 and 370 °C, and TSL spectra heated at 250 and 370 °C had the peak at around 390 nm owing to the Ce3+ ions. TSL dose response functions showed linear response from 0.01 mGy to 10 Gy for the 1.0% Ce-doped mullite single crystal and from 0.1 mGy to 10 Gy for the 0.1, 0.5, and 1.5% Ce-doped ones. The 1.0% Ce-doped mullite single crystal could be used multiple times for dosimetry. In addition, the TSL intensity of the 1.0% Ce-doped mullite single crystal after 7 days from X-ray irradiation was about 82.4% from immediately one after X-ray irradiation.
•We have synthesized Ce-doped Al4SiO8 single crystals by floating zone method.•We have characterized the photoluminescence, and thermally stimulated luminescence.•All the samples showed luminescence properties due to the 5d-4f transitions of Ce3+.•The lower detection limit of the 1.0% Ce-doped Al4SiO8 single crystals was better than those of a part of commercial dosimeters.
Optical, scintillation, and dosimetric properties of the undoped and Tb-doped CaYAlO4 single crystals grown by the floating zone method were evaluated. Several photoluminescence (PL) emission peaks ...due to the 4f–4f transitions of Tb3+ ion were observed at 385–620 nm under excitation at 250 nm in Tb-doped CaYAlO4 samples. Under X-ray irradiation, scintillation peaks of the Tb-doped CaYAlO4 crystals were consistent with the PL emission peaks. In terms of a dosimetric property, the 0.1% Tb-doped crystal exhibited the highest thermally stimulated luminescence intensity and the widest linear responses in the range of 0.01–1000 mGy among the samples.
•The undoped and Tb-doped CaYAlO4 single crystals were synthesized by the floating zone method.•The Tb-doped samples exhibited luminescence due to the 4f-4f transitions of Tb3+.•The 0.1% Tb-doped crystal exhibited the widest linear responses in the range of 0.01–1000 mGy among the samples in TSL.
We synthesized Tm-doped NaMgF3 crystals and investigated their scintillation, optically stimulated luminescence (OSL), and thermally stimulated luminescence (TSL) properties. All the crystals showed ...multiplex luminescence peaks. Judging from the emission wavelength and scintillation decay time constants, Tm3+ acts as a luminescence center in NaMgF3 crystals. The 0.3% Tm-doped crystal showed the highest scintillation, OSL, and TSL intensities. The 0.3% Tm-doped crystal showed a linear relationship from 0.01 to 100 mGy for its TSL dose response function. This lower detection limit is comparable to that of some commercial products. In addition, we succeeded in 2D X-ray imaging using the TSL of the crystal.
We evaluated the photoluminescence (PL), scintillation, and dosimetric properties of Ce–doped Mg
2
SiO
4
single crystals. As the PL and optically-stimulated luminescence (OSL) properties, the ...Ce–doped Mg
2
SiO
4
showed the emission from 5
d
to 4
f
transitions of Ce
3+
. In the scintillation and thermally-stimulated luminescence (TSL) properties, two emission peaks due to Ce
3+
and defect centers were observed. The Ce–doped Mg
2
SiO
4
showed OSL by stimulating at 600 nm and TSL by heating at 50, 160, 195, and 370 °C. In OSL, linearly proportional responses were confirmed from 10 mGy for the 0.5 and 1% Ce–doped samples to 100 mGy for the 0.1% Ce–doped sample. In TSL, the undoped and Ce–doped samples had the linearity response from 100 to 0.01 mGy, respectively.
Eulytite-type Ba3RE(PO4)3 (RE = Y, La, and Lu) single crystals were synthesized by the floating zone method, and their scintillation properties were investigated. The powder X-ray diffraction ...measurement revealed that the single phase of Ba3RE(PO4)3 samples were successfully synthesized. The samples exhibited a luminescence peak due to self-trapped exciton at around 400 nm under vacuum ultraviolet and X-ray irradiation. The X-ray-induced scintillation decay time constants of the samples were several microseconds at room temperature. In the 241Am α-ray irradiated pulse height spectra, all the samples showed a clear full energy peak, and the absolute light yields of the Ba3Y(PO4)3, Ba3La(PO4)3, and Ba3Lu(PO4)3 single crystals were estimated to be 960, 1160, and 1220 ph/5.5 MeV-α, with a typical error of ±10%, respectively. The scintillation light yields of the Ba3RE(PO4)3 have been quantitatively clarified for the first time.
In this study, Mg1.995−xSiO4:xCe, 0.005Tb (x = 0 and 0.01) single crystals were synthesized by the floating zone method and their photoluminescence (PL) and dosimetric properties were evaluated. In ...the PL process, emission peaks due to the 4f–4f transitions of Tb3+ ions were observed in the x = 0 and 0.01 samples, and the emission peak due to the 5d–4f transitions of Ce3+ ions was detected in the x = 0.01 sample. In the thermally stimulated luminescence (TSL) process, only emission peaks due to the 4f–4f transitions of Tb3+ ions were observed in both samples, and the x = 0.01 sample had higher TSL intensity than the x = 0 sample. The x = 0.01 sample showed a lower detection limit of 0.01 mGy and a spatial resolution of 50.0 μm under X-ray irradiation.
We synthesized 20Lu2O3-30Ga2O3-50SiO2 glasses doped with various concentrations of Sn using a floating zone furnace equipped with Xe arc lamps. The samples showed a luminescence band around 450 nm in ...both photoluminescence (PL) and scintillation spectra. The origin of the luminescence was ascribed to the T1–S0 transition of Sn2+ on the basis of the luminescence wavelength and PL decay time constant. The highest scintillation intensity and PL quantum yield were observed from the 1% Sn-doped sample. The afterglow level tended to decrease with increasing Sn doping, and the afterglow levels of the 1 and 3% Sn-doped samples were comparable to that of the conventional Tl-doped CsI scintillator. The optimal concentration of Sn for the glass was estimated to be 1%.
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