| publication name | Linear and nonlinear optical studies of thermally evaporated chalcogenide a-Pb-Se-Ge thin films |
|---|---|
| Authors | Ahmed Saeed Hassanien, Ishu Sharma, Kamal A. Aly |
| year | 2021 |
| keywords | Glassy samples, Amorphous thin films, Optical characteristics, Optical energy gap, Refractive index dispersion, Non-linear optical parameters |
| journal | Physica B: Physics of Condensed Matter |
| volume | 613 |
| issue | Not Available |
| pages | 412985 (1-12) |
| publisher | Elsevier |
| Local/International | International |
| Paper Link | https://www.sciencedirect.com/science/article/pii/S0921452621001848 |
| Full paper | download |
| Supplementary materials | Not Available |
Abstract
This article is dedicated to studying optical characteristics of thermally evaporated Pb10Se90-xGex (0.0 ≤ x ≤ 10.0 at.%) thin films. These films were deposited on pre-cleaned high-quality glass substrates under a vacuum about 5× 10^ -4 Pa. The amorphous nature of films was affirmed by X-ray diffractograms. Elemental analysis was done by Energy-dispersive X-ray spectroscopy. Optical properties of Pb–Se-Ge films were studied and investigated using the transmission spectra. Thickness of the films and refractive index were computed utilizing Swanepoel envelope method. Wemple-Di-Domenico model was applied to get dispersion energies and oscillator parameters. Absorption coefficient values of films were estimated and found to be of the order of 10^ 4cm^-1. The electronic transitions of a-Pb10Se90-xGex thin films were resulted from allowed indirect transitions and the optical band gap was found to decrease from 1.623 eV to 1.538 eV with increasing Ge-ratio while Urbach energy was found to increase from 61 meV to 86 meV. All discussed parameters strongly depend on the Ge-concentration.