File this under: real invisibility cloaks. That’s right, Duke graduate student Nathan Landy’s cloak uses “a similar row-by-row design to previous attempts, but added copper strips to create a more complicated – and better performing – material.” Continue reading for a news report and more information.
When any type of wave, like light, strikes a surface, it can be either reflected or absorbed, or a combination of both. In the case of earlier cloaking experiments, a small percentage of the energy in the waves was absorbed, but not enough to affect the overall functioning of the cloak. The cloak was naturally divided into four quadrants. Landy explained the “reflections” noted in earlier cloaks tended to occur along the edges and corners of the spaces within and around the meta-material.
“We built the cloak, and it worked,” he said. “It split light into two waves which traveled around an object in the center and re-emerged as the single wave with minimal loss due to reflections.” Landy said this approach could have more applications than just cloaks. For example, meta-materials can “smooth out” twists and turns in fiber optics, in essence making them seem straighter. This is important, Landy said, because each bend attenuates the wave within it.