Optical band gap studies on lithium aluminum silicate glasses doped with Cr3+ ions
El-Diasty, F; Abdel-Wahab, Fathy; Abdel Baki, M. H.;
Abstract
Lithium aluminum silicate glass system (LAS) implanted with chromium ions is prepared. The reflectance and transmittance measurements are used to determine the dispersion of absorption coefficient. The optical data are explained in terms of the different oxidation states adopted by the chromium ions into the glass network. It is found that the oxidation state of the chromium depends on its concentration. Across a wide spectral range, 0.2-1.6 μm, analysis of the fundamental absorption edge provides values for the average energy band gaps for allowed direct and indirect transitions. The optical absorption coefficient just below the absorption edge varies exponentially with photon energy indicating the presence of Urbach's tail. Such tail is decreased with the increase of the chromium dopant. From the analysis of the optical absorption data, the absorption peak at ground state exciton energy, the absorption at band gap, and the free exciton binding energy are determined. The extinction coefficient data are used to determine the Fermi energy level of the studied glasses. The metallization criterion is obtained and discussed exploring the nature of the glasses. The measured IR spectra of the different glasses are used to throw some light on the optical properties of the present glasses correlating them with their structure and composition. © 2006 American Institute of Physics.
Other data
Title | Optical band gap studies on lithium aluminum silicate glasses doped with Cr3+ ions | Authors | El-Diasty, F; Abdel-Wahab, Fathy ; Abdel Baki, M. H. | Keywords | FUNDAMENTAL ABSORPTION-EDGE;SPECTROSCOPY;EMISSION;TEMPERATURE-DEPENDENCE | Issue Date | 2006 | Publisher | AMER INST PHYSICS | Journal | Journal of Applied Physics | Volume | 100 | Issue | 9 | ISSN | 0021-8979 | DOI | 10.1063/1.2362926 | Scopus ID | 2-s2.0-33751120377 | Web of science ID | WOS:000242041500024 |
Attached Files
File | Description | Size | Format | Existing users please Login |
---|---|---|---|---|
Optical band gap studies on lithium aluminum silicate glasses (J. Applied Physics).pdf.pdf | 328.17 kB | Adobe PDF | Request a copy |
Similar Items from Core Recommender Database
Items in Ain Shams Scholar are protected by copyright, with all rights reserved, unless otherwise indicated.