New Material, Darker Than Black, Could Help Space Cameras See Better | Popular Science

New Material, Darker Than Black, Could Help Space Cameras See Better | Popular Science: Scientists make Vantablack by depositing carbon nanotubes close together on a thin sheet of aluminum. The tiny spaces between the tubes trap light, preventing it from reflecting off the material. A number of research groups have made super-absorbing black materials with similar microstructures. One advantage of Vantablack is that it doesn't require as high of temperatures to make as other carbon nanotube materials, according to Surrey NanoSystems. That means engineers can deposit Vantablack coatings on a wider range of materials.

Nano Paint Could Make Airplanes Invisible to Radar

Nano Paint Could Make Airplanes Invisible to Radar: This effect works, Guo says, because the nanotubes are perfectly absorbing, and because when they are grown with some space between them, as in his experiments, their index of refraction is nearly identical to that of the surrounding air. This means that light won't scatter out of the nanotubes without being absorbed.

Perfect black coating can render a 3D object flat, raises intriguing dark veil possibility in astronomy

Perfect black coating can render a 3D object flat, raises intriguing dark veil possibility in astronomy: To demonstrate this concept, the researchers made a raised, microscopic tank shape on a piece of silicon. They then grew the carbon nanotube carpet on top of the entire silicon chip. In photos taken through an optical microscope, they show that the tank is imperceptible. As a control, they did this again, carving out a rectangle that was not coated with carbon nanotubes. The rectangle is visible on this chip, but the tank remains hidden.

A Super-Absorbent Solar Material

A Super-Absorbent Solar Material: Atwater worked with Koray Aydin, now an assistant professor of electrical engineering and computer science at Northwestern University, to develop the super-absorber design, which takes advantage of a phenomenon called optical resonance. Just as a radio antenna will resonate with and absorb certain radio waves, nanostructured optical antennas can resonate with and absorb visible and infrared light. The length of a structure determines what wavelength of light it will resonate with. So Atwater and Aydin designed structures that effectively have many different lengths: wedge shapes with pointy tips and wide bases. The thin, nanoscale wedges strongly absorb blue light at the tip and red light at the base.

Atwater and Aydin demonstrated this broadband effect in a 260-nanometer-thick film made of a layer of silver topped with a thin layer of silicon dioxide and finished with another thin layer of silver carved with arrays of wedges that are 40 nanometers at their tips.