In J.K. Rowling’s Harry Potter series, the boy wizard inherited an invisibility cloak from his father. He could use it to sneak around undetected through the stony halls of Hogwart’s School of Witchcraft and Wizardry, to escape the confines of the same place, and to spy on the plots and plans and deeds of other characters in the story. If you’re 8 years old, the thought of your own personal invisibility cloak is highly entertaining.
Enter scientists – presumably older than 8 – at the University of California at Berkeley, who announced this week that they have engineered some nifty “metamaterials” that can bend light rays around an object to render them effectively invisible. The entertaining dream just became reality, but will likely be reserved mostly for spies and other, more lethal tools of military stealth. Alas, we probably won’t be able to buy our own invisibility cloaks at WalMart any time soon.
Research published in Science describes a metamaterial composed of silver nanowires grown inside a porous aluminum oxide. The result is a structure about 10 times thinner than a sheet of paper that can refract light ‘backwards’ to render a cloaked object invisible to human eyes, radar, and near-infrared wavelengths as short as 660 nanometers. Nature looks at a ‘fishnet’ metamaterial and its possibilities.
We should probably not let the Romulans know about this development. Let them invent their own cloaking device!