Optical characteristics of Samarium Sm3 oped Dysprosium Dy3 doped and Sm3 Tb3 co activated phospho tellurite glasses for solid state lighting device applications

Abstract

The Chapter 1 describes the main ambition of the present Ph.D thesis work. Here, the main newlineobjectives behind the study of the structural as well as the photoluminescence characteristics newlineincluding the decay and chromaticity measurements of Sm3+ ions embedded zinc phospho newlinetellurite glasses, Tb3+/Sm3+ co-incorporated phospho-tellurite/tellurite glasses and the Dy3+ newlineactivated phospho-tellurite glasses have been elucidated. Beside it, the principal aspects of their newlineusages in scientific discipline and many technological applications have been mentioned here. newlineIn Chapter 2, the theoretical details about the trivalent rare earth (RE3+) ions have been newlinediscussed. This chapter comprises the free-ion Hamiltonian solving method with the assumption newlineof many types of interactions taking place in-between the partially filled 4f electrons. Even, newlineseveral radiative laser parameters i.e. emission branching ratio, theoretical decay time, stimulated newlineemission cross section, optical gain and bandwidth have been evaluated utilising the obtained JO newlineparameters. In addition to it, the procedure to assess the oscillator strength of all possible electric newlineand magnetic allowed transitions is described here. newlineChapter 3 gives the brief description of the previous review work which was reported by newlineseveral researchers. Generally, it represents the emission characteristics, structural studies newlineincluding XRD, FTIR measurements along with the energy migration phenomenon of Sm3+ newlineactivated, Tb3+/Sm3+ co-doped and Dy3+ incorporated in several types of host glass matrices. newlineAlongside, the scope of the present thesis is also expounded here. newlineThe Chapter 4 deals with the glass processing method (melt quenching technique) of Sm3+ newlinedoped, Tb3+/Sm3+ co-doped and Dy3+ activated various phospho-tellurite/tellurite glasses and newlinealso the annealing procedure of each glass series. In this chapter, the experimental techniques to newlineperform different experimental measurements i.e. DTA, XRD, FTIR, Optical absorption, newlinephotoluminescence including the equipme