If too many rare-earth ions are crammed into the glass structure of a fiber, without careful incorporation of network modifiers (which are co-dopants to aid the creation of sites), the ions can cluster together. This means they are more likely to interact together, in processes such as pair induced quenching, rather than be useful in the active medium. Clustering can also disrupt the molecular structure of the lattice to such an extent that the glass devitrifies, which make the fiber very brittle, and in extreme cases essentially distributes grains of sand throughout the core – badly affecting the fibers performance as a gain medium.


Related Terms: Active Medium, Amplified Spontaneous Emission, Clustering, Co-Operative Up-Conversion, Core, Erbium Doped Fiber (EDF), Erbium, Non-Radiative Decay, Quantum Conversion Efficiency, Spontaneous Emission