Studies on Er2O3 Dy2O3 doped zinc borotellurite glasses

Abstract

Rare earth (RE3+) elements are well known for their exceptional properties and industrial applications. They play important role in the modern optoelectronic industries. RE doped glasses have many applications such as in high power lasers and as radiation shielding materials. Most of the glass lasers use RE3+ ions as active sites because of low coupling of the RE3+ with the host vibrations. The host required for laser applications must have very less phonon energy. For this purpose tellurite glasses are considered as excellent choice because of their least phonon energy amongst all the other oxide glasses. The present work deals with the preparation of Er2O3/Dy2O3 doped zinc borotellurite glasses. The effect of different processing conditions like heat treatment and gamma irradiation on the structural, optical and luminescent properties of such glasses is studied in detail. The entire thesis is divided into eight chapters; the outline of each chapter is given below: Chapter 1 The optical properties of the RE doped glasses are important for their applications. The present chapter describes the luminescence properties of materials and their associated mechanisms. Since the work deals with tellurite and borate glasses a brief introduction of glasses and their properties which get affected by heat treatment and gamma irradiation have been presented in this chapter. Chapter 2 summarizes the literature review on the tellurite glasses. This chapter gives introduction about the work done by different researchers to prepare pure tellurite glasses. It also discusses about the discrepancies found in various parameters like transition temperature and density of pure TeO2 glasses. In continuation it discusses about the mixed former and effect of modifiers on the tellurite glasses. This chapter also gives information about the effect of dopants like rare earths and metal nano particles on the luminescent properties of the tellurite glasses.