Investigations on the spectroscopic properties of Dy3+ ions doped Zinc calcium tellurofluoroborate glasses

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 193; pp. 422 - 431
• Main Authors: Karthikeyan, P., Arunkumar, S., Annapoorani, K., Marimuthu, K.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.03.2018
• Subjects: Absorption spectra; Bonding parameter values; Judd-Ofelt theory; Stimulated emission cross-section; XRD; Y/B intensity ratio; Judd-Ofelt theory; Bonding parameter values; Stimulated emission cross-section; Y/B intensity ratio; XRD; Absorption spectra
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2017.12.049

A new series of Dy3+ doped (30–x)B2O3+30TeO2+20CaCO3+10ZnO+10ZnF2+xDy2O3 (x=0.01, 0.1, 0.5, 1, 2 and 3 in wt%) Zinc calcium tellurofluoroborate glasses were prepared and their structural, luminescence and excited state dynamics have been studied and reported. The structural properties have been characterized through XRD and FTIR studies to confirm the amorphous nature and to explore the presence of fundamental stretching vibrations. The bonding parameters (δ and β), optical band gap, Urbach's energy, oscillator strengths and Judd-Ofelt (JO) intensity parameters were calculated from the absorption spectra. The JO intensity parameters and the Y/B intensity ratio values have been used to explore the nature of the bonding and asymmetry around the Dy-ligand field environment. The luminescence properties of the present Dy3+ doped glasses have been analyzed through luminescence excited state dynamics and radiative properties such as transition probability (A), stimulated emission cross-section (σPE) branching ratio (β) and radiative lifetime (τR) values. The combination of dominant blue (4F9/2→6H15/2) and yellow (4F9/2→6H13/2) emissions generates white light emission in the CIE chromaticity diagram thus suggests that the present Dy3+ doped glasses are suitable for white light applications. The lifetime of the 4F9/2 excited state is found to decrease with the increase in Dy3+ ion content and the concentration quenching of the Dy3+ ions emission could be ascribed due to the resonant energy transfer and cross-relaxation processes. The non-exponential behavior of the decay curves has been analyzed with Inokuti-Hirayama model and the interaction between the Dy3+ ions is of electric dipole-dipole in nature. [Display omitted] •The bonding parameter studies reveal the ionic nature of the metal-ligand bond in the title glasses.•The higher Ω2 values indicate the presence of lower symmetry around the Dy3+ ion site.•The 0.5DZCTFB glass is favorable for low-threshold, high gain applications utilized to obtain continuous wave laser action.•CIE values of the prepared glasses suggested for white light applications.