"Invisibility cloaks cast in chalcogenide glass can render objects invisible to infrared frequencies of light, according to researchers at Michigan Technological University...Most other demonstrations of invisibility cloaks have used metamaterials composed of free-space split-ring resonators that were constructed from metal printed-circuit board traces surrounded by traditional dielectric material. The Michigan Tech researchers...claim that by substituting nonmetallic glass resonators made from chalcogenide glass, infrared cloaks are possible too..."
This story also has some other details about how invisibility cloaks work and predicts further developments will eventually realize Harry Potter style cloaks. I'm still not convinced that such cloaks would really be undetectable, but at least its fun to read about how seriously these researchers are taking the adage: 'Any sufficiently sophisticated technology is indistinguishable from magic,' Arthur C. Clarke.
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