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The growing interests in fibre lasers, amplifiers and sensors have led to the need for fabricating preforms and fibres with the given concentration of rare-earth ions and composition of the host matrix. Several techniques have been developed, of which the solution doping process to incorporate rare-earth ions into the core of fibre is now most widely used. In.this technique rare-earth ions are introduced from solutions and a number of modifications to the conventional MCVD process allow the incorporation of dopant ions from solution. In this paper, we report measurements of the R.I. profile, distribution of rare-earth ions in the silica matrix, Photoluminescence spectra of the rare-earth ions in the silica matrix as a function of composition of matrix and absorption spectra for preforms and fibers made through solution doping technique. The soot was deposited in such a way that it forms a porous and adherent layer suitable for solution doping. A detail thermochemical calculation has been worked out to ascertain reaction kinetics including temperature for completion of reaction, efficient deposition and dehydration of soot. Calculation shows higher refractive index is obtained for a given flow rate of GeCl4 in a solution doped preform than the conventional MCVD preform. NJ/OJ has been used in place of Cl2/02 and it gives reasonable dehydration efficiency to remove -OH ions. The effectiveness of the dehydration procedure is confirmed by the very low -OH ion absorption loss around 1390nm. The rare-earth doped preforms and fibres with different core compositions (GeO2-SiO2, GeO2-Al2O3-SiO2, Al2O3-P2O5-SiO2 and P2Os-SiO2) fabricated have been characterised by measuring the R.I. profile, attenuation and fluorescence spectra. The doped fiber shows the change in relative intensity of the absorption peak for different host composition. Strong fluorescence has been observed at around 1536 nm for Er3+ ion in Ge02-Si02 host glass. However, the peak changes its position and shape when A1 put in the host.
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