Erbium (III) ions- doped borate based glasses for 1.53 μm broad band applications

Designed and synthesized a novel erbium (III) ions doped borate based glasses (Er³⁺ : BCNF) by conventional melt-quenching technique. The glasses were characterized for their structural, vibrational and spectroscopic properties. The nephelauxetic ratio, bonding parameters, and Judd-Ofelt (JO) intensity parameters (Ω_λ λ = 2, 4 and 6) were determined by using absorption spectrum of 1 mol% Er₂ O₃ doped glass. These JO parameters were utilized to derive radiative properties for various excited states of Er³⁺ ions. Emission cross-section for ⁴ I_13/2 → ⁴ I_15/2 transition of erbium (III) ions was computed through McCumber theory. The decay curves for (² H_11/2 , ⁴ S_3/2 ) and ⁴ I_13/2 levels were recorded and analysed. All the results of Er³⁺ : BCNF glasses revealed that the studied glasses are efficient and thermally stable, could be suitable for display devices, optical amplification and green lasers applications.

Structural and optical absorption studies on Cr2O3 doped SrO-P2O5 glasses

Cr₂O₃ doped glasses in the system xCr₂O₃-(60-x) P₂O₅-40SrO, where x = 0.0, 0.025, 0.05, 0.1, 0.2, 0.4 & 0.6 mol% were prepared and investigated by X-ray, UV-Vis, and FT infrared spectroscopy. According to the X-ray data, no sharp peaks can be observed, but only abroad halo which points the amorphous nature of the glass samples. Optical absorptions have shown that Cr ions are present in two possible oxidation states (trivalent & hexavalent). Increasing Cr₂O₃ concentrations in the glass network cause a reduction in the indirect and direct optical energy gap of prepared samples from 3.94-3.5 eV and 4.92-4.4 eV, respectively. This behavior is related to the network forming ability of Cr₂O₃. FTIR spectra of Cr₂O₃ containing glass showed some differences compared to base glass samples. In addition, calculated physical and optical parameters reveals a close similarity to base glass that can be correlated to the minor addition of Cr₂O₃.

Effect of annealing temperature on optical properties of binary zinc tin oxide nano-composite prepared by sol-gel route using simple precursors: structural and optical studies by DRS, FT-IR, XRD, FESEM investigations

Binary zinc tin oxide nano-composite was synthesized by a facile sol-gel method using simple precursors from the solutions consisting of zinc acetate, tin(IV) chloride and ethanol. Effect of annealing temperature on optical and structural properties was investigated using X-ray diffraction (XRD), diffuse reflectance spectra (DRS), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD results revealed the existence of the ZnO and SnO2 phases. FESEM results showed that binary zinc tin oxide nano-composites ranges from 56 to 60 nm in diameter at 400°C and 500°C annealing temperatures respectively. The optical band gap was increased from 2.72 eV to 3.11 eV with the increasing of the annealing temperature. FTIR results confirmed the presence of zinc oxide and tin oxide and the broad absorption peaks at 3426 and 1602 cm(-1) can be ascribed to the vibration of absorptive water, and the absorption peaks at 546, 1038 and 1410 cm(-1) are due to the vibration of Zn-O or Sn-O groups in binary zinc tin oxide.

Study on optical properties of l-valine doped ADP crystal

Single crystal of l-valine doped ammonium dihydrogen phosphate has been grown by slow evaporation method at room temperature. The crystalline nature of the grown crystal was confirmed using powder X-ray diffraction technique. The different functional groups of the grown crystal were identified using Fourier transform infrared analysis. The UV-visible studies were employed to examine the high optical transparency and influential optical constants for tailoring materials suitability for optoelectronics applications. The cutoff wavelength of the title crystal was found to be 280nm with wide optical band gap of 4.7eV. The dielectric measurements were carried to determine the dielectric constant and dielectric loss at room temperature. The grown crystal has been characterized by thermogravimetric analysis. The second harmonic generation efficiency of the grown crystal was determined by the classical Kurtz powder technique and it is found to be 1.92 times that of potassium dihydrogen phosphate. The grown crystal was identified as third order nonlinear optical material employing Z-scan technique using He-Ne laser operating at 632.8nm.