Optical Absorption of Chalcogenide Glass Ga<sub>2</sub>S<sub>3</sub>-La<sub>2</sub>S<sub>3</sub> Doped with Erbium
oleh: V. V. Halyan, A. H. Kevshyn, I. A. Ivashchenko, I. D. Olekseuk, I. V. Danyliuk, G. P. Shavarova
| Format: | Article |
|---|---|
| Diterbitkan: | Vasyl Stefanyk Precarpathian National University 2018-01-01 |
Deskripsi
<span>The glasses of the La</span><sub>2</sub><span>S</span><sub>3</sub><span>-Er</span><sub>2</sub><span>S</span><sub>3</sub><span>-Ga</span><sub>2S3</sub><span> system were synthesized from the melted samples which where quenched in to the cold 25% solution of NaCl. Their optical absorption spectra were studied in the range of 1.2–2.9 eV at 80 K. For doped erbium glasses, there are narrow absorption bands with maxima at 2.53, 2.35, 2.27, 1.88, 1.54, 1.26 eV. With increasing of the content of La<sub>2</sub>S<sub>3</sub> (30 - 40 mol. %) the bandgap width decreases (Eg = 2.83 - 2.73 eV) and the Urbach parameter increases (</span><img src="http://www.pu.if.ua/inst/phys_che/start/pcss/vol18/images/anote1803_13_htm_eqn2254.gif" border="0" alt="" /><span>E = 151 - 238 meV). These changes are determined by the structural disorder in the glasses. </span><br /><strong>Keywords: </strong><span>glassy alloys, optical absorption, Urbach's rule.</span>