Sm 3+ /Yb 3+ Co-doped Sodium Tellurite Glass: Optical and Structural Properties

1. Sm3+/Yb3+ Co-doped Sodium Tellurite Glass: Optical and Structural Properties Fakhra Nawaz Md. RahimSahar, S. K. Ghoshal, Ishaq Ahmed Email: miss_fakhra_nawaz@yahoo.com Advanced Optical Material Research Group, Faculty of Science, UniversitiTeknologi Malaysia

2. Presentation Outlines Introduction Motivation Objective Methodology Results and Discussion Significances Conclusion Future outlook Acknowledgement

3. Introduction • Concentration dependant optical and structural behavior of glasses is important for • Optical amplifiers • Solid state lasers • Optical fiber • Tellurite glasses are promising material due to • Low phonon energy • Better thermal and chemical stability • High refractive index • Good infrared transmission etc.

4. Motivation We got this motivation from “Spectroscopic studies of Sm3+ and Eu3+ co-doped lithium borate glass” Because of great enhancement in the Absorption intensity Photoluminescence intensity Elfayoum et al. Journal of Alloys and Compounds ,492 (2010) 712–716

5. Objectives • To synthesis a series of glasses • To characterize structurally and optically. • To study the effect of co-doping on present glasses • To compare with existing literate

6. Methodology (79.5-x) Te2O-20Na2O-xSm2Cl3-0.5Yb2O3 (0.5 mol% ≤ x ≤ 2.0 mol%) Glass Preparation Melt quenching techniques Optical Characterization UV-VIS-NIR and PL spectroscopy Structural Characterization XRD and FTIR spectroscopy

7. Absorption Spectra • Superposition of Sm3+ :6H5/2→6F11/2 and Yb3+: 2F7/2→2F5/2 • transition in the range of ~825-1030 nm. • Intensity of absorption bands is Sm3+ ion concentration • dependant.

8. Experimental oscillator strength Babuet al. Journal of Alloys and Compounds 509 (2011) 4743-4747.

9. PL Spectra (477 nm excitation) • Four transitions of Sm3+ ion 4G5/2 → 6H5/2, 6H7/2, 6H9/2 and • 6H11/2 • Intensity of emission bands is Sm3+ ion concentration • dependant

10. Energy Level Diagram

11. FWHMof Emission Bands {4G5/2 → 6Hj/2(j=5, 7, 9, 11) transitions} Lakshminarayana et al. Physic B, 404 (2009) 1169-1188 .

12. FTIR Spectra Two transmission bands at 615 cm-1 and 748 cm-1 representing stretching vibration of TeO4 tbp and TeO3 tp The bands at 1600cm-1 and 3350 cm-1are assigned to the stretching vibration of the hydroxyl group

13. Significance • Concentration dependant Optical and structural behavior of glasses understood . • From FWHM and oscillator strength we assert, tellurite glasses may be promising materials for optical devices such as • Solid state lasers • Optical amplifiers • LEDS • etc

14. Conclusion • Nine absorption peaks of Sm3+ion and one peak Yb3+ • Oscillator strength increases with Sm2Cl3 contant • Three strong and one weak emission peaks are observed • FWHM and intensity of emission peaks is dopant concentration dependant. • FTIR transmission bands at 615 cm-1 and 748 cm-1 to the stretching vibration mode of TeO4 tbp and TeO3 tp. • Promising material for photonic devices application

15. Future outlook

16. Acknowledgement We gratefully acknowledge UTMand MOHEfor financial support under the Vot of 4F083 I also thanks Experimental Physics Labs, NCP, Islamabad, Pakistan, for granting me study leave for PhD.

18. Thanks