New Rare Earth Ion-Doped Hosts for Broadband Fibre Amplifier

Three kinds of oxide glasses doped with Er3+ ions were chosen for investigation. Both the properties of glass and fluorescence from rare earth dopant ions are measured and discussed. In Er3+ ion doped silicate glass, the changes in the structure of glass as a result of fluorine addition are studied by measuring the glass properties: density, molar volume, refractive index, IR and UV edges. The absorption and emission cross- sections of Er3+ ion increase with increasing value of F/O ratio as do the full width of half maximum (FWHM) and figure-of-merit (FOM) for gain and bandwidth. In Er3+ ion doped heavy metal germanate glass, the structural units of forming network in germanate glass change with the addition of PbO, Bi2C>3, Ga2C>3 and TeC>2. The molar volume, glass transition temperature Tg, IR and UV edges have been measured and discussed with the relation of glass structure. More Er3+ ion sites result in the increase of absorption and emission cross-sections, emission FWHM and FOM for gain. In Er3+ doped Te02 - ZnO - R2O (R2O = Li20, Na20 and K2O) tellurite glass system, glass properties such as density, molar volume, transition temperature Tg, IR and UV edges are measured and discussed. The glass structure has been characterised using Raman spectra. The role of F' and Cl' has also been studied in tellurite glass. Crystallisation kinetics has been analysed in tellurite glass using isothermal and non- isothermal methods. The properties of Er3+ absorption and emission have been measured and discussed with the change of glass structure and concentrations. FOM for gain and bandwidth have also been compared and discussed in Er3+ doped modifies silicate, HMO germanate, tellurite and ZBLAN fluoride glasses. The tellurite glass fibre has been made and the emission spectra of Er3+ ion in fibre have been measured. Absorption and emission spectra have been studied in Tm -doped tellurite glass, it shows to be a highly promising host for a 1.47 (im amplifier capable of providing extended short-wavelength gain and a continuous band with the tellurite EDFA. Nd3+- doped tellurite and silicate glasses have also been studied, amplifier operating around 1.34 (j.m is clearly desirable in tellurite glass. A continuous gain band extending from 1310 to 1600 nm may become possible by using Nd3+, Tm3+ and Er3+ amplifiers.