US Patent 7771619 - Transparent inorganic nanoparticle composite for low loss telecomm fiber

http://ip.com/patent/US7771619

This patent from Rutgers has some early priority (1999) to optically transparent nanomaterial composites useful for constructing fiber optic cables of low attenuation. Claim 1 reads:

1. Solid solution inorganic nanoparticles of a rare earth element doped host metal halide or oxyhalide salt, wherein up to about 60 mole percent of said host metal is replaced with one or more rare earth elements, consisting of particles having a dispersed particle size less than 100 nm.