PREPARATION AND CHARACTERIZATION OF RARE EARTH ION DOPED LUMINESCENT MATERIALS FOR OPTOELECTRONIC DEVICE APPLICATIONS

Abstract

Potassium Zinc Alumino Borosilicate (KZABS) glasses doped with different concentrations of various rare-earth ions such as Sm3+, Eu3+, Dy3+, Tb3+ and Tm3+ ions were prepared by the conventional melt quenching technique. The glassy nature of KZABS host glass has been confirmed through XRD measurements. FT-IR and Raman spectra for the KZABS host glass have been recorded to know the presence of various functional groups and phonon energy of the host glass. FT-IR spectrum helps to evaluate the OH content present in the host glass. Archimedes’ principle and Brewster’s angle method were employed to estimate the physical parameters such as density and refractive index for the as-prepared glasses, respectively. The optical absorption, excitation, emission and lifetime measurements were carried out to find the suitability of these glasses for designing and developing various optoelectronic devices. Absorption spectra were used to estimate the energy bandgap of the synthesized glasses. The PL emission profiles were subjected to Dexter’s theory in order to elucidate the mechanism involved in the energy transfer process between various rare-earth ions. The Inokuti-Hirayama model was applied to the PL decay profiles one mare in order to understand the energy transfer mechanism and confirm the conclusions of Dexter’s theory. The temperature-dependent emission profiles have been recorded to check the thermal stability of the as prepared glasses. Further, it will also be used to evaluate the activation energy of the as-prepared glasses. Furthermore, CIE chromaticity coordinates were also evaluated to understand the suitability of these glasses for various visible emission applications. CIE points help to assess the color purity and color-correlated temperature of the as-prepared glasses. All these parameters are essential to know the suitability of these glasses for various photonic device

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applications such as solid-state lightings, fiber amplifiers and white light emitting diodes (w LEDs).