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The research work emphasizes on physical and luminescence properties of oxide and oxyfluoride phosphate glasses and discusses the energy transfer between Gd3+ and Sm3+ ions. Lithium gadolinium oxide and oxy-fluoride phosphate glasses doped with Sm3+ ions were prepared by conventional melt quenching technique. Subsequently the physical and luminescence properties were investigated systematically to understand their behavior. The density of the prepared glass samples show high in oxide glasses as compared to oxy-fluoride glasses, and the density of both glass samples increase with increase in the Sm2O3 concentrations. In total, ten signature Sm3+ ion peaks were observed in the UV-Vis-NIR absorption spectra. In photoluminescence spectra the oxy-fluoride glass samples show higher excitation and emissions intensity than oxide glasses. The emission intensity increases up to 1mol% concentration of Sm3+ ions and then decreases due to non-radiative energy transfers. The same is observed in case of radioluminescence emission spectra. The calculated J-O intensity parameters show Ω2 > Ω4 > Ω6 trend. From Judd-Ofelt analysis, these glasses exhibit high potential for using as laser host medium. The life time recorded at the excitation and emission wavelength 401 nm and 598 nm respectively and it is observed that the life time decreases with increase in the Sm3+ ions concentration. The CIE coordinates positioned in the orange region of CIE diagram. The properties evaluated in the present work indicate that these glasses can be a good candidate of orange LEDs applications.

Trivalent europium doped aluminium phosphate glasses with different alkali oxides (Li2O, Na2O and K2O) have been prepared by melt quenching technique at 1200 °C. Photoluminescence properties of the obtained glasses have been studied and characterized. Also, Absorption and radiative properties of glasses are evaluated using the Judd–Ofelt (JO) theory. The emission spectra of all glasses remain the characteristic emission peak of Eu3+ with a dominant peak at 612 nm, corresponding to the 5D0 → 7F2 transition by monitoring an excitation wavelength at 393 nm. In the present glass system it was found that lithium oxide has higher intensity of emission spectra than sodium oxide and potassium oxide. The JO intensity parameters (Ω2, Ω4, Ω6) and subsequent radiative properties for the 5D0 → 7FJ (J = 1,2,3,4) transitions are determined. These glasses have potential candidate in the development as red laser source applications.

Erbium (Er) doped P2O5-K2O3-Al2O3:Er2O3 glasses (KPEr) with different contents of Er3+ ions were fabricated by famous melt-quenching technique. The fabricated samples were characterized by using physical, X-ray photoelectron spectroscopy (XPS), photoluminescence, absorption, and J-O analysis techniques. The XRF analyses were performed in order to know the change in elemental composition of fabricated glasses, while using the various concentrations of Er3+ ions. Three emission peaks were observed, two peaks in visible regions of 526 nm (2H11/2→4I15/2) and 550 nm (4S3/2→4I15/2) and one peak in near infrared (NIR) region of 1545 nm (4I13/2→4I15/2). Nine peaks were observed in absorption spectra in the range of 390–1800 nm. The trend of JO parameters for the present KPEr6 glass sample is Ω2> Ω4> Ω6. Higher values of stimulated emission cross-section σemi(λ), full wave half maxima FWHM and (FWHM x σemi (λ)), for KPEr6 indicate that the present glass has potential candidate to be used for broadband amplification in telecommunication. The McCumber theory is used to study absorption and emission cross-section for 4I13/2→4I15/2 transition. The luminescence colors of these samples were almost entirely fall in the yellow-green (Y-G) region (x = 0.33, y = 0.64) in the CIE 1931 diagram. The calculated CCT values for our prepared glasses were found to be 5554 K. The present study suggest that KPEr glass samples have potential candidate for broadband amplification in telecommunication, green LED and display devices.

Europium (Eu3+) doped glasses of chemical compositions (55−x)B2O3:10SiO2:25Y2O3:10CaO:xEu2O3, 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 (Ωλ) 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 (AR), branching ratio (βR), stimulated cross section emission (σ) and radiative lifetime (τR) for 5D0 → 7FJ (J = 0,1,2,3 and 4) transitions. The decay rate of 5D0 fluorescent level for all the glass samples was single exponential. Lifetimes of the 5D0 level were decreased with increasing concentrations of Eu3+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.

In this work, the optical and luminescence properties of Dy2O3 doped barium phosphate glass with different alkaline earth oxides (MgO, CaO and SrO) have been investigated. The glass samples were prepared by the melt-quenching technique at the melting temperature of 1200 °C. The absorption spectra of glasses were recorded in the ultraviolet, visible and near infrared (UV-Vis-NIR) region. The absorption bands centered at 385, 424, 452, 472, 754, 803, 901, 1093, 1273 and 1683 nm, respectively have been observed. The emission spectra of glass samples centered at 482, 574, 662 and 751 nm, respectively have been observed with 350 nm excitation wavelength. The result of radioluminescence spectra were slightly different with photoluminescence spectra. The coordinate of emitting color (x, y) for 350 excitation wavelength is 0.3781 and 0.4252, respectively which is located in white light region of CIE diagram.

Bismuth borophosphate glasses containing different doping cerium oxide have been synthesized at 1200 °C by melt-quenching technique. The doping concentration of the Ce3+ was varied from 0.05 mol% to 2.0 mol%. The glass samples were characterized through optical absorption and luminescence spectral measurements. UV-visible and near infrared absorption spectra of glass samples were not observed nevertheless the absorption edge was shift to the longer wavelength. The photoluminescence and radioluminescence spectra show emission bands around 367 nm under 317 nm excitation wavelength. Also, the highest emission intensity was found at 0.5 mol% CeF3 dopant for both of photoluminescence and radioluminescence.

The Er3+-doped calcium barium phosphate glasses with chemical composition 30CaO:20BaO:(50-x)P2O5:xEr2O3 (where x = 0.05, 0.10, 0.50, 1.00 and 2.00 mol%) were prepared by melt-quenching technique. The optical and NIR luminescence properties of the glass samples were investigated to determine the ability for using as broadband optical amplifier. The density, molar volume and refractive index were carried out. The absorption spectra showed 10 absorption bands corresponding to the transitions assigned by 4I15/2→4G11/2 (349 nm), 2G9/2 (403 nm), 4F5/2 (451 nm), 4F7/2 (488 nm), 2H11/2 (522 nm), 4S3/2 (544 nm), 4F9/2 (651 nm), 4I9/2 (803 nm), 4I11/2 (977 nm) and 4I13/2 (1537 nm). Judd-Ofelt analysis was applied in this work and found that the J-O parameters of the CaBaPEr20 glass are 7.44, 2.52 and 4.36 (x 10-20 cm2) for Ω2, Ω4 and Ω6, respectively. Oscillator strength, radiative transition possibility, stimulated emission cross section and branching ratio were also evaluated. NIR luminescence spectra of the CaBaPEr20 glass under 977 nm excitation wavelength showed broad NIR emission band with the peak centered at 1541 nm (corresponding to 4I13/2→4I15/2 transition) in the range of 1455 to 1620 nm covers the S, C and L bands of optical amplifier. The gain bandwidth of optical amplifier calculated by the product of full width at half maximum and stimulated emission cross section was found to be 511 x 10-28 cm3 that relatively high compared with other Er3+-doped systems, indicated the present CaBaPEr20 glass ability for using as broadband optical amplifier at 1.54 µm. Excitation and emission spectra of the luminescence in visible region were also investigated in this work.

Physical, optical and luminescence properties of lithium aluminium phosphate (LAPSm), sodium aluminium phosphate (NAPSm) and potassium aluminium phosphate (KAPSm) glasses doped with 0.5 mol% of Sm2O3 have been investigated. The results found that all glass samples are clear, homogenous and transparency. The optical absorption spectra are shown strong absorption bands in the visible (VIS) and near-infrared (NIR) region for all doped samples. The emission spectra of all doped glass samples exhibited four peaks correspond to the energy transition 4G5/2 → 6H5/2 (562 nm), 4G5/2 → 6H7/2 (597 nm), 4G5/2 → 6H9/2 (644 nm) and 4G5/2 → 6H11/2 (704 nm) have been observed under 401 (6H5/2 → 6P3/2) nm excitation wavelength. Also, the CIE chromaticity analysis yields reddish-orange light emission for all glass samples. It was observed that the emission intensity LAPSm glass is higher than NAPSm and KAPSm glasses. Hence LAPSm glass could be considered as a good optical glass for Sm3+ dopant for reddish-orange emission material.

Sm3+ doped lithium aluminium phosphate glasses have been investigated in different concentration of Sm3+ ions. The physical, optical and luminescence properties were studied to evaluate their potential to using as orange color emitting materials. The result of physical properties indicated that the density, the molar volume and the refractive index of glass samples were increased with an increase of Sm2O3 content. The absorption spectra of glass samples were recorded in the wavelength range of 250-2000 nm. The absorption bands centered at 401, 473, 947, 1080, 1232, 1379, 1482 and 1532 nm have been observed. From the photoluminescence spectra, the glasses are showed strong emission at 597 nm which corresponds to 4G5/2→6H7/2 transition under excitation wavelength at 401 nm. The optimal concentration of Sm2O3 in lithium aluminium phosphate glasses was 0.5 mol%.

Barium borophosphate (BaO-B2O3-P2O5) glasses doped with Sm3+ ions were produced by melt quenching procedure. The doping concentration of the Sm3+ was varied from 0.2 mol% to 1.0 mol%. The obtained glasses were characterized through optical absorption and photoluminescence (PL) spectral measurements. The emission spectra corresponding to the Sm3+: 4G5/2 → 6H5/2 (562 nm), 4G5/2 → 6H7/2 (597 nm), 4G5/2 → 6H9/2 (643 nm) and 4G5/2 → 6H11/2 (704 nm) transitions were obtained under excited wavelength at 401 nm. The photoluminescence intensities of all glasses are comparable and the strongest intensity peak at 597 nm was obtained with 0.4 mol% Sm3+ ions. In order to identify the emission color of the prepared glasses, the emission intensities were analyzed using the 1931 CIE chromatic color coordinates.

The effects of La2O3 based glasses in the glass formula (80-x) B2O3: 10SiO2: 10 CaO: x La2O3 where x = 10, 15, 20, 25, 30 and 35 mol% have been fabricated by a melt-quenching technique, and have been investigated for physical, optical, and radiation shielding properties. The density of the glass was found to increase with increasing concentrations of La2O3. The optical spectra were measured by a UV-Visible spectrophotometer, and this glass has been shown to have advantages due to good transparency. The cut off wavelengths for glass samples with increasing La2O3 concentration are found to shift toward longer wavelengths. The experimental value of mass attenuation coefficient (µm), and the effective atomic number (Zeff) of the glass samples increases with increasing levels of La2O3 concentration. Additionally, the effective electron density (Ne) of the glass samples was investigated between 224 to 662 keV. The total µm, Zeff and Ne of the glasses decreases exponentially toward higher energy of gamma-rays and they are in agreement with theoretical values. These results are good indications of the potential of the prepared lanthanum calcium silicoborate glasses as a radiation shielding material with lead-free advantages.

The Dy 3+ -doped yttrium calcium silicoborate glasses of composition of 25Y 2 O 3 + 10CaO + 10SiO 2 + (55-x)B 2 O 3 + x Dy 2 O 3 , where x = 0.05, 0.1, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%, have been synthesized and are characterized through optical, photoluminescence and X-ray induced luminescence properties. The Judd-Ofelt model has been adopted to evaluate the radiative properties of the 4 F 9/2 → 6 H J (J = 15/2, 13/2 and 11/2) emission transitions. The concentration quenching effect of Dy 3+ ion concentration on the emissions from the 4 F 9/2 excited level is discussed in details. The luminescence decay curves of the 4 F 9/2 level transform from exponential to non-exponential nature for higher Dy 3+ ion concentration. The yellow to blue (Y/B) intensity ratio, CIE Chromaticity coordinates and correlated color temperatures (CCT) were calculated from the emission spectra and were found that they fall in yellowish white light region. Thus, these results showed that the present YCaSBDy glasses could be aptly suitable for cool white light emitting diodes as well as glass scintillation applications.

Dysprosium (Dy3+) doped glasses of the potassium aluminum gadolinium phosphate (KAGP) were fabricated by melt-quenching technique. The preparation of glasses was varied the concentrations of Dy2O3 at 0.00, 0.05, 0.10, 0.50, 1.00 and 3.00 mol%. The physical and spectroscopic properties were investigated for white light emitting devices. The absorption spectra were attributed to Dy3+ transitions from the 6H15/2, ground state to the various excited states and found that the intensity of absorption spectra was increased with increasing Dy2O3 concentration. The Judd-Ofelt (JO) intensity parameter Ωλ (λ = 2, 4 and 6) were estimated from the absorption spectra of 0.50 mol% Dy2O3 doped KAGP glass and found to be Ω2 > Ω4 > Ω6. The photoluminescence (PL) spectra were record under 350 nm and showed four intense peaks at 482, 573, 664 and 753 nm which correspond to the excited states (4F9/2) to 6H15/2, 6H13/2, 6H11/2 and 6H9/2 respectively. The intensity of emission spectra increased with content of Dy3+ ions until 0.5 mol% in KAGP glasses and beyond concentration quenching was observed. From the emission spectra have evaluated chromaticity co-ordinates CIE 1931 and observed that the emission of KAGP glasses was in the white region. The results approve that the Dy3+ doped KAGP glasses could be considered for optoelectronic devices such as lasers and white light emitting diode (w-LEDs). The radioluminescence (RL) spectra were measured and show the strongest emission from X-rays excitation at 0.5 mol% of Dy2O3. In evaluation of scintillation property between 0.50 mol% of Dy2O3 doped KAGP glass and BGO crystal, the integral scintillation efficiency was 9% of BGO. It can be potential for integration mode of scintillation such as in medical and industrial X-ray imaging applications.

Cerium-doped lithium barium gadolinium phosphate glass to with various concentration of Gadolinium and cerium have been investigated for this physical and optical properties. The density was determined by Archimedes' principle showed the relation of density and reflective index which depended on Gd2O3 and CeF3 concentrations. Their optical properties were investigated by luminescence spectra under UV and x-rays excitations. The emission and excitation spectra of Ce3+ ion exhibited strong intensity at 338–346 nm (λEX = 302 nm) and at 332–342 nm (λEX = 302 nm) with the concentration of Gd2O3 at 18 %mol for various concentration of Gd2O3 and concentration of CeF3 at 1.0 mol%, respectively. The UV–Vis transmission spectra showed the red shift with the higher concentration of Gd2O3. The oxidation of Ce3+ ions and Ce4+ ions of samples were demonstrated by using X-ray Absorption Near Edge spectroscopy (XANE). In addition, the decay time of samples are very short, in the range of 14–16 ns, which is an important property to improve to the radiation detector. The energy loss by alpha particle was calculated by SRIM program. The result showed the stopping ions range were increased with increasing of alpha energy.

In current study Neodymium doped phosphate glasses were prepared and subsequently the Physical and luminescence properties of these glasses were thoroughly analyzed. In total, eleven absorption bands centered at 352, 431, 474, 512, 526, 583, 626, 683, 746, 803 and 875 nm were observed in absorption spectra. Similarly, the emission spectra of the prepared glasses recorded with 804 nm excitation show three radiative transitions peaks at 873, 1054 and 1333 nm. The luminescence properties of present glasses analyzed theoretically as several radiative properties studied through Judd-Ofelt theory. The emission cross section for 4F3/2→4I11/2 transition of Nd3+ ions, measured to be 11.2 × 10−20 cm2 in the case of oxide and 13.10 × 10−20 cm2 in the case of oxyfluoride glass. Similarly, the calculated and measured branching ratio for oxide glass are 54% and 51% respectively, and for oxyfluoride glass the calculated and measured branching ratios are 53% and 55% respectively. From the FTIR spectra it is noted that the bands correspond to the OH group show low transmittance intensity in oxyfluoride glass than oxide glass which is an evident of low OH contents oxyfluoride glass. In conclusion, from the results of present study reveal that the oxyfluoride glasses reported in present work can be a possible material for laser applications.

This work aimed to study the effect of Gd2O3 and CeF3 modified on potassium gadolinium phosphate glasses scintillators in 17K2O: xGd2O3: (82.5-x)P2O5: 0.5CeF3 (where x = 9, 11, 13, 15 and 17 mol%) and 17K2O: 17Gd2O3: (66-x)P2O5: xCeF3 (where x = 0.1, 0.3, 1, 1.5, 2, 3 and 5 mol%) systems produced by the melt quenching technique. The physical, optical, and scintillation properties of the specimens were measured and discussed. The density and molar volume of the glasses trend to increases with increasing Gd2O3 concentration, while an invariable for all CeF3 concentration. The photoluminescence and x-ray luminescence spectrums show the highest value at 9 and 17 mol% of Gd2O3 concentration, respectively, which shows the decay time between 15.02 and 22.84 ns. XANES results shows the main oxidation state of Ce is 3+ ion for all glasses. However, the photoluminescence and x-ray luminescence spectrums show the maximum value at 5 mol% of CeF3 concentration, which shows the fast decay time between 16.26 and 36.02 ns. These results of the x-ray induced luminescence and the fast decay time in nanoseconds level are possible applied as well as the scintillation materials for radiation detector application.

This paper reports on the physical, optical and photoluminescence properties of Nd3+ doped calcium barium phosphate (CaO:BaO: P2O5) and strontium barium phosphate (SrO:BaO: P2O5) prepared by the melt-quenching technique at 1200 °C. The density and the molar volume of glass samples were carried out at the room temperature. The results show that the density of glasses tends to increase with increasing concentration of Nd2O3. While, the molar volume of glasses tends to decrease with increasing Nd2O3 contents. The absorption spectra of glass samples centered at 351, 431,463, 473, 514, 526, 581, 628, 683, 747, 804 and 874 nm, respectively were observed in the ultraviolet, visible and near-infrared region. The luminescence spectra of glass samples were investigated in near-infrared region. It was observed that the luminescence spectra of glass samples were dependent on Nd2O3 content. Also, the comparison of calcium and strontium with different of Nd3+ concentration is addressed.

Neodymium (Nd 3+ ) doped calcium barium phosphate glasses have been studied in different concentration of Nd 3+ ions. The absorption and luminescence spectra, the Judd–Ofelt (JO) intensity parameters Ω 2,4,6 and other radiative properties, which is radiative transition probabilities ( A R ), stimulated emission cross-sections (σ(λ p ) and branching ratios ( β R ) were calculated. These glass samples have shown strong absorption bands in the visible (VIS) and near-infrared (NIR) region. The emission spectra of glass samples have exhibited three emission transitions, which are assigned to 4 F 3/2 → 4 I 9/2 , 4 F 3/2 → 4 I 11/2 and 4 F 3/2 → 4 I 13/2 transitions, respectively. Also, the results obtained were compared with reports on similar glasses.

Barium borophosphate glasses doped with five concentrations of Er2O3 were prepared by a melted-quenching process. The properties of glasses have been investigated through density, molar volume, absorption and emission spectra measurements. The obtained density and the calculated molar volume values increased with increasing Er2O3 contents. The absorption spectra of glasses were found to have eleven absorption bands at 362 (4I15/2→4G9/2), 379 (4I15/2→4G11/2), 407 (4I15/2→2G9/2+4H9/2), 450 (4I15/2→4F5/2), 488 (4I15/2→4F7/2), 521 (4I15/2→2H11/2), 544 (4I15/2→4S3/2), 652 (4I15/2→4F9/2), 803 (4I15/2→4I9/2), 978 (4I15/2→4I11/2) and 1537 nm (4I15/2→4I13/2). At 521 nm excitation wavelength, the photoluminescence spectra showed highest peak around 1530 nm (4I13/2→4I15/2). The emission intensity depends on Er3+ ion concentration and shown higher emission intensity with increasing concentration of Er2O3.

This research reports on the physical and optical properties of three series of borophosphate glasses combined with barium oxide (BaO), following BaBP-A, BaBP-B and BaBP-C, that were prepared by a melting and quenching process. The density, molar volume, refractive index and absorption spectra were investigated the effect of BaO on different glass structures. The results show that the densities and refractive index of the glass samples increased as the BaO (BaBP-A and BaBP-B) and B2O3 (BaBP-C) mole percentage increased. The molar volume of the glasses shows the adversative trend as the density: the molar volume decreased as the BaO and B2O3 content increased. The absorption spectra of all glass samples were slightly shifted to the longer wavelength, ultraviolet 250-350 nm, with increasing the concentration of BaO.

This paper reports on physical, optical and photoluminescence properties of Sm3+doped calcium barium phosphate (CaO: BaO: P2O5: Sm2O3) glass systems. The glass samples have been prepared by the melt-quenching technique at 1200°C. It was found that the density of glasses tended to increase with increasing of Sm2O3 concentration. While, the molar volume of glasses tended to decrease with increasing of Sm2O3 concentration higher than 0.1 mol%. The absorption spectra of glasses were recorded in the ultraviolet visible near infrared (UV-Vis-NIR) region. The absorption bands centered at 374, 402, 416, 438, 473, 527, 946, 1083, 1236, 1382, 1483, 1531 and 1977 nm, respectively have been observed. The emission spectra of glass samples centered at 561, 597, 643 and 704 nm corresponding to the energy levels from 4G5/2 to 6H5/2, 6H7/2, 6H9/2 and 6H11/2, respectively have been observed with 402 nm excitation wavelength.

In this research, the magnesium bismuth phosphate glasses doped with different concentration of Sm2O3 have been prepared using the melt quenching method at 1200 °C. Magnesium bismuth phosphate glasses are clear, homogenous and increased yellow color with increasing the concentration of Sm2O3. Physical and optical properties of glass samples were investigated. The results show that, the density and molar volumes were increased with increasing the concentration of Sm2O3. The absorption spectra in the wavelength range at 200 - 2500 nm was observed. It was found that the absorption bands have nine peaks with corresponding to 401, 439, 472, 945, 1081, 1231, 1378, 1480 and 1533 nm. Absorption bands at 401 and 1231 nm are highest absorption spectra in visible and near infrared region, respectively. For the luminescence spectrum of glass samples has shown four emission transitions at 562 (green), 598 (orange), 664 (red) and 705 nm with excitation wavelength at 401 nm. The wavelength at 401 and 598 nm has shown highest intensity of excitation and emission wavelength, respectively.

Dysprosium doped lithium lanthanum borate glasses (LiLaB:Dy3+) were prepared by the melt quenching technique, varying the Dy2O3 doped concentration from 0.00 to 1.50 mol%. The absorption spectra showed that LiLaB:Dy3+ glass absorbed photon in visible light and near infrared region. From the excitation of 388 nm, this glass emitted the photon with 483, 575, 664 and 753 nm wavelength. The intensity of emission increased with increasing of Dy2O3 concentration until 1.0 mol%, after that it decreased. The Judd-Ofelt (J-O) analysis was applied to 1.0 mol% doped glass to investigate the J-O parameter, radiative transition possibility and stimulated emission cross section. These values were interpreted to the ability of laser gain medium.

Calcium yttrium silicoborate glasses doped with different Nd3+ ion concentrations have been prepared using the melt quenching technique at 1400 °C. Physical, optical and luminescence properties of glass samples were investigated. The density and molar volume measurements were carried out at room temperature. The results show that, the density and molar volume of glass samples not deepened on the concentration of Nd2O3. Absorption spectra were investigated in the UV–VIS–NIR region from 200 to 2500 nm. It was observed that the absorption bands have 8 peaks with corresponding to 467, 521, 584, 638, 682, 747, 805 and 877 nm. The luminescence properties were investigated in the NIR region. On excitation, with 584 and 805 nm, it is found that the emission peaks are located at 896 (904), 1060 and 1332 nm that correspond to the emission transitions from 4F3/2 to 4I9/2, 4I11/2 and 4I13/2, respectively. The NIR luminescence intensity obtained with 584 nm excitation was stronger than 805 nm.

Er3+ ions doped bismuth borophosphate glasses are prepared in different concentration by the conventional melting-quenching method at 1200 °C. Physical properties, absorption and luminescence spectra under visible excitation are investigated. The results showed that density of glasses tended to decrease with increasing the concentration of Er2O3. While, the molar volume of glasses tended to increase with increasing the concentration of Er2O3. The optical absorption spectra were clearly observed in ultraviolet (UV), visible light (VIS) and near infrared (NIR) region. Visible emission spectra have been recorded by exciting the glass samples at 326 nm. The strongest intensity was the green emission at 521 nm. The luminescence intensity was found to increase with Er2O3 content up to 0.8 mol% and it was decreased for higher Er2O3 contents due to concentration quenching effect.

The present study reports the preparation and analysis of physical, luminescence and structural properties of Dy2O3 doped phosphate glasses. The density and refractive index demonstrate increasing tendency as Dy2O3 concentration increased. The luminescence concentration quenching point is observed at 1.0 mol% of Dy2O3 and 17 mol% of Gd2O3 concentration, when monitored at 350 nm and 275 nm respectively. Similarly, the Judd-Ofelt (JO) theory used to calculate JO intensity parameters (Ω2, Ω4 and Ω6). These parameters show Ω2>Ω4>Ω6 trend. It is recorded that 4F9/2 → 6H13/2 transition has higher values of transition probabilities, branching ratio and emission cross-section parameters. The calculated and experimental results for the radiative properties were compared with each other and with previous reported studies. The decay time is obtained with the emission and excitation of 573 and 350 nm respectively and it is found that, the decay time decreases with increasing Dy3+ concentration. Photoluminescence decay curve analysis and Radio luminescence (X-ray source) decay curve analysis was analyzed. The prepared samples were studied through XANES and EXAFS analysis to understand the local environment of Gd and Dy atom. Gadolinium and Dysprosium show +3 oxidation states in the present glass. Bond distance of Gd–O and Gd–Gd decreases with increase in Gd2O3 content.

Sodium gadolinium phosphate oxide and sodium gadolinium oxyfluoride glasses doped with europium oxide were synthesized by melt-quenching method. The density, molar volume and refractive index of the glass samples were carried out. Density and molar volume of oxide glass is more than oxyfluoride glass. The average phosphate to phosphate distance for oxide glass seems to be more than oxyfluoride glass. Polaron radius, inter-ionic radius shows 1.181 nm, 2.88 nm and 1.174 nm, 2.86 nm for oxide glass and oxyfluoride glasses respectively. Oxide electronic Polarizability and optical basicity of the oxide glass are lower than oxy-fluoride glass. Theoretical optical basicity shows higher for oxide glass than oxyfluoride suggesting increase in covalency of the cation to oxygen bonds in oxide glass. Optical band gap was estimated and found to be 3.061eV and 3.204 eV for oxide and oxyfluoride glass. Theoretical two photon absorption coefficient β were evaluated and found to be 11.96 and 10.80 for oxide and oxyfluoride glasses respectively. Electron-phonon coupling strength were evaluated from the phonon side band spectra for the oxide and oxy-fluoride glasses. The asymmetry ratio (R) show higher for NaF doped glass than Na2O confirming their role in elevated ionicity for oxyfluoride glass than oxide glass. Furthermore, the glasses were subjected to study for their luminescence properties of the oxide and oxyfluoride glass samples.

Sodium gadolinium phosphate oxide and sodium gadolinium oxyfluoride glasses doped with europium oxide were prepared by melt-quenching technique. The physical, optical properties of the glass samples were studied. The density, molar volume and refractive index of the glass samples were carried out. Density and molar volume of oxide glass is more than oxyfluoride glass. The average phosphate to phosphate distance for oxide glass seems to be more than oxyfluoride glass. Polaron radius, inter-ionic radius shows 1.181 nm, 2.88 nm and 1.174 nm, 2.86 nm for oxide glass and oxyfluoride glasses respectively. Oxide electronic Polarizability and optical basicity of the oxide glass are lower than oxy-fluoride glass. Theoretical optical basicity shows higher for oxide glass than oxyfluoride suggesting increase in covalency of the cation to oxygen bonds in oxide glass. Optical band gap were estimated and found to be 3.061eV and 3.204 eV for oxide and oxyfluoride glass. Theoretical two photon absorption coefficient β were evaluated and found to be 11.96 and 10.80 for oxide and oxyfluoride glasses respectively. Furthermore, the glasses were subjected to study for their luminescence properties of the oxide and oxyfluoride glass samples.

Borophosphate glasses have been synthesized with a Bi2O3concentration of 15.0 to 25.0 mol%, added 2.5 mol% for each concentration, by the normal melt quenching technique at 1200 °C. The physical and optical properties of bismuth borophosphate glass systems have been studied. The glasses are characterized for their physical and optical properties. The density and molar volume of these glasses were found in the range 3.4391 to 3.9338 g/cm3and 52.2515 to 55.7557 cm3/mol, respectively. It was observed that the density and molar volume of these glasses was increased with increasing the concentration of Bi2O3. The absorption spectra of these glasses were recorded in the UV-Visible range. It has been found that, the absorption spectra were shifted to longer wavelength with higher Bi2O3concentration. In addition, the oxygen packing density of glass samples have been also investigated.

The lithium lanthanum borate glasses doped with Dy2O3 were prepared by the melt quenching technique. The Dy2O3 doped concentration has been increased and substituted B2O3 from 0.00 to 1.50 mol% in the glasses. The photoluminescence, optical absorption and physical properties of these glasses have been investigated in this work. The experimental results show that, the molar volume of glasses tended to increase with increasing of Dy2O3 concentration, but the density were not depending on the concentration of Dy2O3. The UV-Vis-NIR spectra, absorption bands at 451, 798, 894, 1085 1264 and 1676 nm have been observed. For Dy3+ doped glasses, emission bands centered at 483, 575 and 664 nm have been observed with 388 nm excitation wavelength. The emission spectra have shown the strongest band in the glasses with 0.50 mol% Dy2O3 concentration.

The bismuth borophosphate glass matrix doped with Nd2O3have been prepared by conventional melt quenching method with the molar compositions of 25Bi2O3: 5B2O3: (70-x)P2O5: xNd2O3(where x = 0.2, 0.4, 0.6, 0.8 and 1.0 mol%). The density, molar volume, optical absorption and upconversion luminescnece spectra were studied. It can be seen that the density is not depend on Nd2O3concentration. The molar volume is tending to be decreased with increasing of Nd2O3due to the decrease in the bond length or interatomic spacing between the atoms. Ten absorption bands at 427, 471, 510, 525, 580 , 622, 682, 743, 802 and 873 nm are observed, which could be ascribed to Nd3+transitions from the4I9/2ground state to2P1/2,2G9/2,4G9/2,4G7/2,4G5/2+2G7/2,2H11/2,4F9/2,4F7/2+4S3/2,4F5/2+4H9/2and4F3/2levels. The upconversion luminescence band at 394 nm was observed and the highest emission intensity was obtained at 0.8 mol% of Nd2O3.

This research studied the effect of dysprosium on the physical, optical and luminescence properties of the bismuth borosilicate glass in compositions 40Bi2O3 : 20SiO2 : (40-x)B2O3 : xDy2O3 (where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%). The glass systems have been prepared at 1100 °C by melt quenching technique. The results showed that the density and molar volume of glass samples are between 4.6477 ± 0.0020 to 5.0047 ± 0.0041 g/cm3 and 45.6608 to 48.6797 cm3/mol, respectively. The values of density and molar volume of these glasses were not depend on the Dy2O3 concentration. The optical absorption spectra of glass samples in the UV-Vis-NIR region shows absorption bands at 794, 906, 1094, 1276 and 1690 nm, respectively. The photoluminescence spectra show emission bands at 482 (blue), 576 (green), 663 (yellow) and 756 (red) nm under 453 nm excitation wavelength. The emission spectrum at 576 nm has shown a strongest intensity.

The photoluminescence and physical properties of lithium yttrium borate glasses doped with Eu2O3were studied in this work. The glasses were prepared by the melt-quenching technique and varied the Eu2O3doped concentration between 0.00-1.50 mol%. We found that, the molar volume and density of these glasses showed linear increasing tendency with Eu2O3concentration. The absorption bands were observed in UV and NIR region. For the Eu3+doped glasses, the excitation bands centered at 363, 383, 394, 414, 465, 526 and 533 nm were observed with 613 nm emission wavelength. While in the emission spectra, the bands centered at 590, 613, 652 and 701 nm were observed with excitation of 394 nm. The intensity of excitation and emission bands increased with increasing of Eu2O3concentration.

Gamma-ray exposure buildup factor (EBF) values and neutron shielding effectiveness of bismuth borosilicate (BBS) glass systems in composition (50− x )SiO 2 :15B 2 O 3 :2Al 2 O 3 :10CaO:23Na 2 O: x Bi 2 O 3 (where x =0, 5, 10, 15 and 20 mol%) were calculated. The EBF values were computed for photon energy 0.015–15 MeV up to penetration depths of 40 mfp (mean free path) by the geometrical progression (G-P) method. The EBF values were found dependent upon incident photon energy, penetration and bismuth molar concentration. In low- and high-energy photon regions, the EBF values were minimum whereas maximum in the intermediate-energy region. The fast neutron removal cross sections for energy 2–12 MeV were calculated by the partial density method. The BBS glass with 20 mol% Bi 2 O 3 is found to be superior gamma-ray and neutron transparent shielding. The EBF values of the BBS glasses were compared with steel–magnetite concrete and lead. The investigation was carried out to explore the advantages of the BBS glasses in different radiation shielding applications.

Physical, optical, and luminescence properties of Nd3+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-x)B2O3 : 40Bi2O3 : 20BaO : xNd2O3(wherex= 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 between4F3/2 → 4I9/2(900 nm),4F3/2 → 4I11/2(1,060 nm), and4F3/2 → 4I13/2(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 (λex=591 nm). The processes are associated with excited state absorption (ESA) from4F3/2level to4D3/2level and it is the radiative decay from the4D3/2to ground levels (4D3/2 → 4I13/2) which are responsible for the emission at 394 nm.

Barium borophosphate glasses doped with dysprosium oxide had been fabricated by conventional melt quenching technique using the chemical composition of: (25BaO: 5B 2 O 3 : 70-xP 2 O 5 : xDy 2 O 3 )), where (x = 0.2, 0.4, 0.6, 0.8 and 1.0, mol%) (BaBPDy). The physical, optical and luminescence properties are studied for possibility of using as a white luminescence materials for solid-state light emitting devices. Judd-Ofelt (JO) theory is applied to study the radiative properties of the luminescence level of Dy 3+ ions. The effect of the concentration quenching due to increase in Dy 3+ ions is discussed in details. The lifetime of all BaBPDy concentration glass is bi-exponential in nature, which is discussed in the present work. This non-exponential nature of the decay curve was fitted by using the well-known Inokuti-Hirayama (IH) model S= 6, indicating that the energy transfer process is dipole-dipole type. The chromaticity co-ordinate(x, y) is evaluated from the luminescence spectra and its possibility for using as a white light application has been analyzed.

The new glass series were prepared in compositions 25Gd2O3-10CaO-10SiO2-(55-x) B2O3-xEr2O3 (where x is 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol %) by normal melt-quenching technique at the melting temperature of 1,400 °C. The optical spectra were measured and shown absorption bands were assigned to appropriate f-f electronic transitions of Er3+ ions from the 4I15/2 ground state to the following excited states: 4G11/2, 2H9/2, 4F5/2, 4F7/2, 2H11/2, 4S3/2, 4F9/2, 4I9/2 and 4I11/2. Single peak from upconversion luminescence was observed at 531 nm (green) is assigned to the 2H11/24I15/2. In this work, the strongest peak at 2.0 % mol of Er2O3 was observed. In this work, suggests that the Er3+ ion in gadolinium calcium silicoborate glasses possibly considered as a potential candidate for applications in upconversion-based optical devices.

Visible luminescence of Pr3+ ions in bismuth borate glasses doped with difference concentration of Pr2O3 have been studies. The glasses of composition 30Bi2O3 : (70-x)B2O3 : xPr2O3 (where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) were prepared by the melt quenching technique. The spectral properties were investigated using the absorption and emission measurement. These glasses have shown emission and excitation bands in visible region. The emission band of Pr3+ doped glass centered at 600 nm (1D23H4), 642 nm (3P03F2) and 704 nm (3P03F3) have been observed with 469 nm (3H43P1) excitation wavelength. The excitation band revealed centered at 447, 469 and 482 nm corresponding to the 3H43P2, 3P1 and 3P0 transitions, respectively.

Barium sodium silicoborate glasses with different concentrations of BaO have been prepared by melt quenching technique at 1400 °C. Mass attenuation coefficient; effective atomic number and half value layer have been investigated by using gamma-ray at 662 keV photon energies. These parameters have been compared with theoretical calculation base on XCOM. The results show that the coherent scattering and photoelectric absorption of glasses have increased while the Compton scattering has decreased with increasing of BaO contents. However, Compton scattering gives dominant contribution to the total mass attenuation coefficients for the glasses. Good agreement has been observed between experimental and theoretical computation. Radiation shielding properties of the glasses have been compared with commercial window and ordinary concrete.

In this paper the optical and photoluminescence properties of Dy3+ doped magnesium barium phosphate (MgO-BaO-P2O5; MgDy) glass systems have been reported in different concentration of Dy2O3. The glass samples were prepared by the conventional melt-quenching technique at 1200 °C. The absorption spectra at 446, 753, 804, 901, 1092, 1272 and 1680 nm respectively were observed in the visible and near-infrared region. The emission spectra of Dy3+ doped glasses centered at 482, 574, 662 and 751 nm, respectively have been observed with 350 nm excitation wavelength. Also, Judd-Ofelt (J-O) parameters Ωλ (λ = 2, 4 and 6) have been calculated for all glass samples.