‘Invisibility Cloak’ Ranked in Time Magazine’s 'Best Inventions of 2011' Published June 14, 2013 By Robert White Office of Scientific Research ARLINGTON, Virginia -- In February 2012, a program co-funded by the Air Force Research Laboratory was chosen by Time Magazine for inclusion in its "Best Inventions of 2011" issue. Drs. Ali Aliev, Yuri Gartstein and Ray Baughman, of the University of Texas at Dallas (UTD), produced what has been called an 'invisibility cloak,' technically referred to as the "mirage effect from thermally modulated transparent carbon nanotube sheets." The key to this breakthrough is carbon nanotubes--the successful result of another ongoing Air Force Office of Scientific Research-funded UTD program--that have the ability to disappear when rapidly heated. This effect is because of 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 looks 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. This unique characteristic of nanotube sheets may one day result in applications such as photo-deflectors and switchable transparency materials, as well as use as thermoacoustic projectors and sonar.