Linear and non-linear photoluminescence studies of Ho3+/Yb3+ co-doped titanate phosphors for photonic applications

Abstract

This work presents the morphological and photoluminescence (PL) studies of the single ion Ho3+ doped and Ho3+/Yb3+ co-doped Ba3−x-yMoTiO8:xHo3+/yYb3+ phosphors synthesized by conventional solid-state reaction method. Phase confirmation of all the as-prepared samples was done by X-Ray Diffraction (XRD) patterns. The morphological behavior and vibrational frequency bands were studied by Scanning Electron Microscope (SEM) and Fourier Transform Infrared (FT-IR) techniques respectively. Diffuse Reflectance Spectra (DRS) has been recorded for the singly doped and co-doped samples to find out the optical bandgap. The linear and non-linear emission spectral studies under 448 and 980 nm excitation wavelengths respectively showed three bands in the green, red, and blue regions. A relatively more intense band observed in the green region under 980 nm excitation shows promising usage of the titled phosphor for non-linear applications. A plot drawn between non-linear luminescence emission intensity Vs pump power reveals the information pertaining to the number of photons involved in the process. In addition, Commission Internationale de I′Eclairage (CIE) coordinates calculated from the emission spectral features lie in the green region. All the studies show the broad application of the as-prepared phosphors in linear and non-linear luminescence process-based green emitting diodes, display devices, security inks, phototherapy, and solid-state lighting (SSL) applications.