sporkme writes "A new nanocoating material developed by a team of researchers from Rensselaer Polytechnic Institute has the lowest level of reflectivity ever seen, or not seen in this case. The amount of light reflected by the composite of silica nanorods and aluminum nitride is almost the same amount reflected by air. From the article:
Suggested applications include increased efficiency in solar cells, more energy-efficient lighting and advances in quantum mechanics. No word yet on invisibility cloaks."
Using a technique called oblique angle deposition, the researchers deposited silica nanorods at an angle of precisely 45 degrees on top of a thin film of aluminum nitride, which is a semiconducting material used in advanced light-emitting diodes (LEDs). From the side, the films look much like the cross section of a piece of lawn turf with the blades slightly flattened.