Scientists at the University of St. Andrews, United Kingdom, reported the first development of a truly invisible material in the New Journal of Physics on November 7. 2010.
Although cloaks designed to shield objects from both Terahertz and Near Infrared waves have already been designed, a flexible material designed to cloak objects from visible light poses a greater challenge because of visible light’s smaller wavelength and the need to make the metamaterial’s constituent part – meta-atoms – small enough to interact with visible light.
In a process called optical conformal mapping or transformation optics (TO) metamaterials have been structured to produce a near invisible flexible sheet.
The St. Andrews’ research team, led by EPSRC Career Acceleration Fellow Dr. Andrea Di Falco, have developed an elaborate technique which frees the meta-atoms from the hard surface (‘substrate’) they are constructed on. The researchers predict that stacking them together can create an independent, flexible material, which can be adopted for use in a wide range of applications.
Dr. Di Falco commented, “Metamaterials give us the ultimate handle on manipulating the behavior of light. The impact of our new material Meta-flex is ubiquitous. It could be possible to use Meta-flex for creating smart fabrics placed on disposable contact lenses to create superlenses that could further enhance vision. Typical lenses generally have some form of limitation, such as aberration or limited resolution, but these perfect lenses would have none of these deficiencies.
Flexible metamaterials at visible wavelengths
Andrea Di Falco, Martin Ploschner and Thomas F Krauss School of Physics and Astronomy, University of St. Andrews, North Haugh, KY16 9SS, Fife, UK