polarization tagged posts

Controlling Light with a Material Three Atoms Thick

Controlling Light With a Material Three Atoms Thick

Thin structures made of black phosphorus can tune the properties of light, with implications for science and technology. Most of us control light all the time without even thinking about it, usually in mundane ways: we don a pair of sunglasses and put on sunscreen, and close — or open — our window blinds.

But the control of light can also come in high-tech forms. The screen of the computer, tablet, or phone on which you are reading this is one example. Another is telecommunications, which controls light to create signals that carry data along fiber-optic cables.

Scientists also use high-tech methods to control light in the laboratory, and now, thanks to a new breakthrough that uses a specialized material only three atoms thick, they can control light more precisely than ever bef...

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Making 3D objects Disappear: Ultrathin Invisibility Cloak created

This image shows a 3-D illustration of a metasurface skin cloak made from an ultrathin layer of nanoantennas (gold blocks) covering an arbitrarily shaped object. Light reflects off the cloak (red arrows) as if it were reflecting off a flat mirror. Credit: Image courtesy of Xiang Zhang group, Berkeley Lab/UC Berkeley

This image shows a 3-D illustration of a metasurface skin cloak made from an ultrathin layer of nanoantennas (gold blocks) covering an arbitrarily shaped object. Light reflects off the cloak (red arrows) as if it were reflecting off a flat mirror. Credit: Image courtesy of Xiang Zhang group, Berkeley Lab/UC Berkeley

It conforms to the shape of an object and conceal it from detection with visible light. Although this cloak is only microscopic in size, the principles behind the technology should enable it to be scaled-up to conceal macroscopic items as well.

Working with brick-like blocks of gold nanoantennas, the Berkeley researchers fashioned a “skin cloak” barely 80nm in thickness, that was wrapped around a 3D object about the size of a few biological cells and arbitrarily shaped with mul...

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