Optical spectroscopy and emission properties of Ho^{3 +}-doped gadolinium calcium silicoborate glasses for visible luminescent device applications

• Main Authors: Kesavulu C., Kim H., Lee S., Kaewkhao J., Wantana N., Kothan S., Kaewjaeng S.
• Format: Journal
• Published: 2017
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85028365278&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/40083
• Institution: Chiang Mai University

© 2017 Elsevier B.V. The Ho 3 + -doped gadolinium calcium silicoborate glasses with the composition of 25Gd 2 O 3 + 10CaO + 10SiO 2 + (55 − x)B 2 O 3 + xHo 2 O 3 , where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%, were synthesized by well-known melt quenching method. These glasses have been characterized through physical, structural, optical, visible emission and decay curve analysis. From the absorption spectrum, Judd-Ofelt intensity parameters for 1.0 mol% Ho 2 O 3 doped glass have been carried out and were used to examine radiative properties for the important visible emitting levels of Ho 3 + ions. The present Ho 3 + :glasses show strong green emission at 545 nm and red emission at 655 nm under excitation at 452 nm. The radiative decay time and stimulated emission cross-section for the ( 5 S 2 , 5 F 4 ) → 5 I 8 transition are found to be 280 μs and 0.63 × 10 − 20 cm 2 , respectively. Decay curves for all the concentration of Ho 3 + ions exhibit non-exponential nature for ( 5 S 2 , 5 F 4 ) → 5 I 8 transition. The decrease in decay times is due to the resonant energy transfer among the excited Ho 3 + ions. Hence, these results confirm that the present silicobora te glass system could be considered as a promising candidate for visible green laser applications.