In science fiction stories, the power to become invisible is not rare. Perhaps one of the most well known stories where this occurs is Harry Potter. Wizards can disappear from view simply by covering themselves with an invisibility cloak. What was once considered only possible in the realm of science fiction is now closer to becoming a reality. Scientists at the University of California, Berkeley have developed what they call a “carpet cloak” which allows objects placed underneath it to become undetectable to the eye. The carpet, made from nanostructured silicon, remains visible itself. However, the bulge created by the object hidden underneath appears flat as a beam of light hits the surface of the carpet. Xian Zhang believes that this development can lead to “…manipulating light at will for the creation of powerful new microscopes and faster computers.” Zhang and his team had previously found that complex metamaterials can be used to bend light backwards. The team had attempted to use these metamaterials to achieve invisibility however it could not be done because the metal elements take in a large amount of light. Eventually the team began working with diaelectric materials and created the new “carpet cloak.” Although invisibility of objects currently occurs for light between 1400 and 1800 nanometers is wavelength, Zhang remains hopeful about what can be achieved in the future. “…with more precise fabrication this all dielectric approach to cloaking should yield a material that operates for visible light - in other words, true invisibility to the naked eye.” (ScienceDaily).
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