Transparent Material Breakthrough: One of Time Magazines Best Inventions of 2011|
by Robert P. White, Ph.D.
Air Force Office of Scientific Research
12/2/2011 - ARLINGTON, Va. -- A program co-funded by the Air Force Office of Scientific Research (AFOSR) was chosen by Time Magazine for its List of Best Inventions of 2011.
Drs Ali Aliev, Yuri Gartstein and Ray Baughman, of the University of Texas at Dallas (UTD), have succeeded in producing what is technically referred to as the "mirage effect from thermally modulated transparent carbon nanotube sheets," or, as some in the popular press have termed it: an 'invisibility cloak'."
The key to this breakthrough are carbon nanotubes--the successful result of another ongoing AFOSR-funded UTD program--that have the ability to disappear when rapidly heated. In reality, this effect is due to photothermal deflection, or a mirage effect, quite similar to what a driver may experience when a highway in the distance becomes so hot that a section of the road may look like a pool of water. This is due to the bending of the light around the hot road surface wherein the driver actually sees the reflected sky in place of the pavement. The carbon nanotubes create much the same effect when heated.
AFOSR funding for this program was critical in enabling nanotube sheet fabrication which offers key advantages for photothermal deflection which permits the transparency effect to take place. This unique characteristic of nanotube sheets may one day result in applications such as photo-deflectors and for switchable transparency materials, as well as their use as thermoacoustic projectors and sonar.
The Air Force Office of Scientific Research, located in Arlington, Virginia, continues to expand the horizon of scientific knowledge through its leadership and management of the Air Force's basic research program. As a vital component of the Air Force Research Laboratory, AFOSR's mission is to discover, shape and champion basic science that profoundly impacts the future Air Force.