New Invisibility Cloak

Until recently, cloaking devices that could render objects invisible were limited to the realm of fantasy or science fiction. Over the last few years, scientists have reported marginal success using bulky metamaterials to divert incoming waves around an object. Now, a new material that’s only a few micrometers thick has been shown to effectively cloak an 18 centimeter rod by canceling out the waves as they scatter off of it.

The new method – called mantle cloaking – uses a metascreen made by attaching ultrathin copper strips to a flexible polycarbonate, fishnet substrate. When irradiated with microwaves, energy fields from the object and the cloak interfere with each other to create a transparent effect.

The technology works best with microwaves at a frequency of 3.6GHz. It could also be used for wavelengths in the visible spectrum, however the size of the object must be scaled to match the wavelength, so at this point in their research it would only be effective on micrometer-sized objects at optical frequencies.