Researchers at Japan's Institute of Physical and Chemical Research have unveiled their prototype of a glass-like material that they claim to be 100% transparent. Unlike normal glass, which reflects some of the incoming light, the new so-called metamaterial --composed of a grid of gold or silver nanocoils embedded in a prism-shaped, glass-like material -- uses its unique structural properties to achieve a negative refractive index, or complete transparency. Although currently just a one-off proof-of-concept (pictured, under an electron microscope), mass-produced versions of the new material could improve fiber optic communications, contribute to better telescopes and cameras, or lead to the development of completely new optical equipment.

I'm not sure this will make that much difference to fiber optics. For fiber optic lines, the point of being nearly transparent is to keep the signal from fading over distance. Even in 1993, though, I was reading about fibers that could carry a terabit in the lab over 3000 miles without repeaters. However, that might have been with optical amplifiers. If you could get rid of those, then long-distance fiber would be even cheaper.