Optical properties of antimony-borate glass rods co-doped with Eu3+/Ag+ ions

This paper presents the results of research on the luminescent properties of antimony-borate glass rods doped with europium and silver ions. The reduction of silver ions to the form of nanoparticles was carried out and the occurrence of localized plasmon resonance was demonstrated, which caused changes in the Eu3+ luminescence signal at a wavelength of 613 nm. The effect of the concentration of silver ions dopant at a constant content of europium ions on the luminescence and absorption characteristics of the produced samples was investigated. In the examined doping range, no large dependencies of spectral changes as a function of the concentration of silver ions were found. A clear quenching of the luminescence was observed due to the heating time of the doped glass matrices for the energy transition (5D0 → 7F2). Full Text: PDF ReferencesS. Kuzman, J. Perisa, V. Dordevic, I. Zekovic, I. Vukoje, Z. Antic and M. D. Dramicanin, "Surface Plasmon Enhancement of Eu3+ Emission Intensity in LaPO4/Ag Nanoparticles", Materials 13, 3071 (2020). CrossRef V.P. Prakashan, M.S. Sajna, G. Gejo, M.S. Sanu, A.C. Saritha, P.R. Biju, J. Cyriac and N.V. Unnikrishan, "Surface Plasmon Assisted Luminescence Enhancement of Ag NP/NWs-Doped SiO2-TiO2-ZrO2:Eu3+ Ternary System", Plasmonics 14, 673 (2019). CrossRef O. Malta, P. Santa-Cruz, G. Sa and F. Auzel, "Fluorescence enhancement induced by the presence of small silver particles in Eu3+ doped materials", J. Lumin., 33, 261 (1985). CrossRef O. Malta, P. Santa-Cruz, G. Sa and F. Auzel, "Time evolution of the decay of the 5Do level of Eu3+ in glass materials doped with small silver particles", Chem. Phys. Lett, 116, 396 (1985). CrossRef J. Zmojda, M. Kochanowicz, P. Miluski et al., "The influence of Ag content and annealing time on structural and optical properties of SGS antimony-germanate glass doped with Er3+ ions", Journal of Molecular Structure 1160, 428 (2018). CrossRef Ki Young Kim, Plasmonics: Principles and Applications (Croatia, InTechOpen 2012) CrossRef M.R. Dousti, M.R. Sahar, S.K. Ghoshal et al., "Up-conversion enhancement in Er3 +-Ag co-doped zinc tellurite glass: Effect of heat treatment", Journal of Non-Crystalline Solids 358, 2939 (2012). CrossRef I. Soltani, S. Hraiech, K. Horchani-Naifer et al., "Effect of silver nanoparticles on spectroscopic properties of Er3+ doped phosphate glass", Optical Materials 46, 454 (2015). CrossRef R. Schneider, E.A. de Campos, J.B.S. Mendes, J.F. Felix, P.A. Santa-Cruz, "Lead–germanate glasses: an easy growth process for silver nanoparticles and their promising applications in photonics and catalysis", RSC Advances 7 (66), 41479 (2017). CrossRef

A prototype anti-scatter detector for megavoltage X-ray imaging

In this work, a prototype anti-scatter detector based on Cherenkov radiation is developed by using glass rods. Scattering lends deleterious effects to the megavoltage x-ray portal imaging and anti-scatter detector can effectively reduce these effects. A 10 cm long glass rod with 1 mm in diameter is used as a Cherenkov detector prototype and it is studied for its response to x-ray scattering from, e.g., machine head and patient. It is subjected to 6 MV x-ray beam generated by linear accelerator (LINAC) with different field sizes (from 3 X 3 to 20 X 20 cm2) at different air gaps such as 10, 30 and 46 cm. The Cherenkov signal created by the detector is transmitted through optical fiber to photomultiplier tube (PMT) and measured by electrometer. The patient scattering is studied by placing a solid water phantom at isocenter. The response of single pixel Cherenkov detector is compared with the conventional ionization chamber detector. It has been observed that glass rod based Cherenkov detector is less sensitive to scatter radiation than ion-chamber for air gap of 10 cm. The Cherenkov signal created by glass rod is quite weak for larger air gaps and the uncertainties are quite high. Moreover, the coupling between Cherenkov detector and optical fiber is quite crucial for transmitting the Cherenkov signal from glass rod into optical fiber.

A prototype anti-scatter detector for megavoltage X-ray imaging

In this work, a prototype anti-scatter detector based on Cherenkov radiation is developed by using glass rods. Scattering lends deleterious effects to the megavoltage x-ray portal imaging and anti-scatter detector can effectively reduce these effects. A 10 cm long glass rod with 1 mm in diameter is used as a Cherenkov detector prototype and it is studied for its response to x-ray scattering from, e.g., machine head and patient. It is subjected to 6 MV x-ray beam generated by linear accelerator (LINAC) with different field sizes (from 3 X 3 to 20 X 20 cm2) at different air gaps such as 10, 30 and 46 cm. The Cherenkov signal created by the detector is transmitted through optical fiber to photomultiplier tube (PMT) and measured by electrometer. The patient scattering is studied by placing a solid water phantom at isocenter. The response of single pixel Cherenkov detector is compared with the conventional ionization chamber detector. It has been observed that glass rod based Cherenkov detector is less sensitive to scatter radiation than ion-chamber for air gap of 10 cm. The Cherenkov signal created by glass rod is quite weak for larger air gaps and the uncertainties are quite high. Moreover, the coupling between Cherenkov detector and optical fiber is quite crucial for transmitting the Cherenkov signal from glass rod into optical fiber.

Optimum Lasing Cavity for Erbium Doped Zinc Tellurite Glass Rods Embedded with Ag Nanoparticles

A laser cavity was constructed for excitation of erbium doped zinc tellurite glass rods embedded with various concentration of Ag nanoparticles. Central to the system is a Xenon flashlamp for optical pumping, and mirrors to amplify the light waves. The amorphousity of the glass rod was studied by X-ray diffraction and the existence of silver nanoparticles inside the glass was confirmed by high resolution transmission electron microscopy analysis. The photoluminescence properties and differential thermal analysis curve of the samples confirmed the compatibility of the rods as gain medium. The rods were successfully fabricated and incorporated inside the laser cavity. The output of the laser with erbium doped zinc tellurite glass rods embedded with Ag nanoparticles was characterized via spectrum analyser and was found that the spectrum dominated at line 473 nm and 506 nm. The beam profiler was utilized to detect and display the laser beam in 3D.

Design of Optical 4 × 2 Encoder Using Cross Layered Chalcogenide2D-PC Resonator

In this paper, 4 × 2 encoder is proposed by combining optical waveguides and the ring resonators. The proposed structure has four input ports, two control input and two output ports. The hexagonal photonic crystal structure has the square lattice of chalcogenide glass rods with the refractive index of 2.1 in air. Maximum bit rate of 10 Tb/s and response time of 0.1 ps is obtained using the proposed cross-layered arrangement of the chalcogenide glass rods with circular inner arrangement. The size of the proposed structure is 18.6 µm x 24.6 µm. Moreover, the contrast ratio of outputs is found to be 28.3 and 48.45 dB. The fundamental structure for the proposed encoder is also designed and analysed for validating the desired bandgap at the resonant wavelength of 1550 nm.

An Optical Half Adder Using Nonlinear Ring Resonator Based on Photonic Crystal

Nonlinear photonic crystal ring resonators are suitable mechanisms that can be used for designing optical logic gates and digital structures. In this paper, we designed two nonlinear resonant rings by adding doped glass rods inside the photonic crystal ring resonator. An optical half adder was designed using these nonlinear photonic crystal ring resonators. We used plane wave expansion and finite difference time domain methods to simulate our optical half adder. The simulations show that when one of the input ports is ON, the normalized optical power at the S is about 90 %. The time delay in this case is 7 ps. Also when both the input ports are ON, the normalized optical power at the C is about 155 %. The time delay in this case is 8 ps.

Flexural properties of sandwich composite laminates reinforced with glass and carbon Z-pins

This study aims to enhance the flexural properties of sandwich composites made from glass or carbon face and glass and carbon fibre Z-pin inserted extruted-polystyrene (XPS) foam cores. Carbon and glass pins were placed through XPS foams with two different column and row densities (15 and 30 mm). Results indicated that flexural loads, strength and modulus of glass/XPS and carbon/XPS sandwich composites significantly increased after inserting of glass and carbon rods. Core shear strengths and facing stresses of glass/XPS and carbon/XPS increased by increasing of carbon or glass rod densities. The rod type, rod density and face type of the sandwich composites are considered as significant parameters which affect the flexural behaviour of sandwich composites while using carbon rods enhanced flexural properties more than that of using glass rods due to better interfacial bonding.