Very Interesting – How to Make a Better Invisibility Cloak—With Lasers

Images: Clockwise from top left: Karlsruhe Institute of Technology; Karlsruhe Institute of Technology/ Nature Materials; Karlsruhe Institute of Technology; Karlsruhe Institute of Technology/Applied Physics Letters
Made From Scratch: Lasers were used to draw the micrometer-scale structures in these metamaterials. Pictured clockwise from top left are a bichiral photonic crystal [top view], a photonic quasicrystal, a bichiral photonic crystal [oblique view], and a pentamode metamaterial.

For a century or more, nearly all technological advances have depended on our ability to produce and manipulate the vast variety of materials that nature has given us. Nowhere is that dependence more evident than in the field of electronics. From a smorgasbord of semiconductors, polymers, and metals, we’ve been able to create a dazzling array of circuitry that now underpins pretty much every aspect of modern life.

So now imagine what we could do if we weren’t limited to the materials found in nature. Researchers have long believed that it would someday be possible to produce artificial materials, or “metamaterials,” and that they would bring about some stunning, otherworldly technologies—the sort that have figured in science fiction tales for years. These innovations include invisibility cloaks that could mask the presence of objects or their electromagnetic signatures, “unfeelability cloaks” that could mechanically mask the tactile feel of an object, superlenses that could resolve features too small to be seen with ordinary microscope lenses, and power absorbers that could capture essentially all of the sunlight hitting a solar cell.

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Graphene Circuit Competes Head-to-Head With Silicon Technology

IBM has built on their previous graphene research and developed what is being reported as the best graphene-based integrated circuit (IC) built to date, with 10 000 times better performance than previously reported efforts.

This graphene-based IC serves as a radio frequency receiver that performs signal amplification, filtering and mixing. In tests, the IBM team was able to use the circuit to send text messages (in this case, “IBM”) without any distortion.

“This is the first time that someone has shown graphene devices and circuits to perform modern wireless communication functions comparable to silicon technology,” IBM Research director of physical sciences Supratik Guha said in a release.

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