Optical and dielectric properties of transparent ZrO2–TiO2–Li2B4O7 glass system

A new series of transparent zirconium titanium lithium diborate glasses of the nominal composition 85 Li2B4O7–(15–x) TiO2– x ZrO2 (x = 0, 5, 10 and 15 mol %) was prepared using melt quenching method. The investigated glasses are characterized in an attempt to determine the effect of different zirconium ion concentrations on their structural, optical and dielectric properties. X-ray diffraction (XRD) patterns confirmed the amorphous nature of the present glass system. The main features concerning the local structure of the present glass system were determined by Fourier transform infrared (FTIR) spectroscopy. The addition of Zr ions to borate glass changed the coordination of borate matrix and consequently converted BO4 to BO3 (BO4→BO3 back conversion effect). Optical transmission and reflection measurements were performed as a function of wavelength, showing highly transparent glasses. The optical constants such as refractive index, extinction coefficient, absorption coefficient and optical band gap were calculated. The actual value of the optical band gap energy for these glasses was established by studying the absorption band profile. The frequency and temperature dependent dielectric constant, dielectric loss and AC electrical conductivity measurements were carried out. Excellent structural and physical, optical and dielectric properties of the present glass system indicate prospects for various photonic devices.