Chao Wang

Er-Doped Fibre Amplifiers (EDFAs) are widely used in space applications because of their immunity to electromagnetic interference, reduced size, lightweight and mechanical flexibility. Their application fields range from optical communications to several on-board navigation instruments. However, their use in harsh environments is strongly limited by their reduced resistance and stability at temperatures above 850^oC and under hard radiation exposure. High temperatures and gamma radiation induce structural and chemical changes, forming non-radiative trapping defects within the fibres which degrade both transmission and optical amplification. This irreversible degradation starts at the nanoscale and propagates up to the macroscale until catastrophic failure occurs. The ideal preventive solution is to reduce the damage induced by radiation by limiting atomic displacement within the fibre during exposure.

The main objective of my project is to develop an innovative and efficient (process) technology that promotes the nucleation of Er-np inside optical fibres with different Erbium dopant concentrations. This will be achieved by testing non-destructive techniques already in use for synthesizing nanocomposites in fused silica matrices and by investigating the effects of such treatments on EDFA microstructures as a function of process parameters. Specifically, three main objectives of this project are as follows: (i) To synthesize Er-np within commercial EDFAs using a post fabrication process; (ii) To characterize and minimize the residual damage generated during each treatment; (iii) To investigate the effect of other dopants, such as Ni, Co, B etc.