The clever chaps at Duke University have been busy beavering away for years to make the sci-fi staple cloaking device a reality, and their recent results mean a real product is closer than ever. They've fabricated a better metamaterial cloak that can make an object effectively invisible by bending light around it—as if the object wasn't there.
A metamaterial is one that's cleverly designed to exhibit particular characteristics from its structure rather than its exact composition, and creating them requires high-power mathematics. The Duke team has been busy refining this aspect of their metamaterial clocking device—first shown in 2006—to create a wholly new product that is far more effective.
To work as a cloak, the metamaterial device bends or distorts light around an object so that an observer sees the view as if the object weren't there. Specifically, cloaking devices like this bend a range of electromagnetic radiations—making the object "invisible" in the infrared and radio-wave sense, for example.
Until now bending visible light has proved tricky, but with the new technique the device "can cloak a much wider spectrum of waves—nearly limitless," according to team leader David R. Smith. The technology was demonstrated by sending microwaves through their etched fiberglass cloak towards a microwave-reflective "bump," and achieved success when the scattered light from the bump was detected behaving as if the bump weren't there. The reflective shape had been completely cloaked by the metamaterial.
And that's likely to be one important application for this technology—a radio-wave cloak could effectively "mask" objects to particular radio frequencies. This has important uses in improving communications, and perhaps even solving the problem of ATC radars being scattered off buildings and other structures.
And, of course, it means invisiblity cloaks for visible light are closer to being made. Harry Potter eat your heart out.