The substance absorbs between 97 percent and 99 percent of wavelengths that can be directly measured or extrapolated. It's the closest that scientists have yet come to a black body, a theorized state of perfect absorption whose closest analogue is believed to be the opening of a deep hole.
The material, described Monday by Japanese nanotechnologists in the Proceedings of the National Academy of Sciences, is made from a flat array of vertically-aligned, single-walled carbon nanotubes. Photons that aren't immediately absorbed by a single nanotube deflect off and are absorbed by its neighbors.
"This interaction," write the researchers, "repeats until the attenuated light is completely absorbed by the forest." To the naked eye, the substance appears perfectly flat; in effect, it's a sheet of deep holes.
By comparison, the blackest paints and coatings absorb between 84 and 95 percent of all light. Researchers say the material would be useful in solar panels or to collect heat in the frigid vacuum of space.
Citation: "A black body absorber from vertically aligned single-walled carbon nanotubes." By Kohei Mizuno, Juntaro Ishii, Hideo Kishida, Yuhei Hayamizu, Satoshi Yasuda, Don N. Futaba, Motoo Yumura, and Kenji Hata.Did you like this post? Leave your comments below!
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