MIT produces new metamaterial that acts as a lens for radio waves

MIT produces new metamaterial ...
The MIT metamaterial lens
The MIT metamaterial lens
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The MIT metamaterial lens
The MIT metamaterial lens
The metamaterial lens and one of the S-black structures
The metamaterial lens and one of the S-black structures
Electromagnetic field amplitude with and without the lens
Electromagnetic field amplitude with and without the lens
Graph of received power after passing through the lens
Graph of received power after passing through the lens
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We expect the world to be predictable. Water flows downhill, fire burns and lenses bend light in a particular way. That worldview took a jolt as Isaac Ehrenberg, an MIT graduate student in mechanical engineering, developed a three-dimensional, lightweight metamaterial lens that focuses radio waves with extreme precision. That may not seem too disturbing, but the lens is concave and works in exactly the opposite manner of how such a lens should.

Metamaterials have an air of magic about them. The elements they’re made out of should work one way, but they way they’ve been fabricated make them operate in another. They are ordinary substances that have been engineered with precisely designed and fabricated microscopic structures. These structures interact with light or sound in such a way that they produce effects that are not found in nature. In the case of the MIT metamaterial lens, they result in a concave lens that should spread radio waves, but focuses them instead.

The metamaterial lens and one of the S-black structures
The metamaterial lens and one of the S-black structures

The lens is produced by blocky, S-shaped “unit cells” a few millimeters wide that refract radio waves in particular directions. The roughly concave lens is formed from 4,000 of these cells. They were fabricated from a polymer by means of 3D printing into a self-supporting structure, and then coated with a fine mist of copper. The 3D fabrication technique meant that there was little energy lost as the radio energy passed through the lens, which was a problem with previous lenses made of stacked 2D structures.

The lens produces a level of focus that is so precise that it has the potential for imaging individual molecules. It also has the advantage of being lightweight, which Ehrenberg claims would make it practical for sending into orbit for astronomical observations.

The results of the MIT team were published by Ehrenberg and his colleagues Sanjay Sarma, and Bae-Ian Wu in the Journal of Applied Physics.

Source: MIT

View gallery - 4 images
Bruce Miller
Tunable to specific frequencies? Shades of Tesla's genius? High voltage power transfer? For high voltage, chemical based electric storage devices? A glimpse into the future? Even more effective systems than low voltage Electric Car batteries as 'buffers" for grids? So much potential , makes a lifetime feel so short! End of high loss transmission lines down the road? All by microwave or higher frequencies, focused? Very exciting indeed!
Joseph Mertens
It makes me think producing the S blocks at the nano scale and coating with a superconductor would yield a greater result.
Fretting Freddy the Ferret pressing the Fret
I cannot wait to see what magic comes out of this new lens. Surprisingly, the first thing that comes up to me is finding natural radio sources farther away in space than possible yesterday.
Crankie Fahrt
Imagine if SETI could up-scale this to the Aricebo dimensions? Awesome!
Walt Stawicki
@ Bruce. unless the material is also one of those flexible ones that are used to create nanomachines, changing with a current...I can't see a grid of them being tunable. The effects are config dependent, how do you poropse that the config is changeable in this almos xtaline matrix? what this reminds me of is butterfly wing and color.
I can see improved tranmission rates over radio links, less loss to noise interfenence without more output power, and it means the power contributes less to noise recieved at other antennae in the area. ghuray!
Which radio waves? All of them from DC-to-Daylight? Radio waves ain't all the same. Their behaviour changes dramatically with frequency. This article lacks some fundamental detail. As a radio radio amateur, I want to know more.
Could this be used to focus coherent sound waves, like a laser does, with light? Could something similar be done with magnetic waves, and create a tractor beam?
Michael Perry
If the focus is as narrow as described, this device might have great potential for medical uses.
1. The tissue in cancer tumors might respond differently to certain frequencies than normal tissue, making it easier to locate.
2. The narrow focus might locate small tumors before they grow large.
3. Using radio waves rather than X-rays would reduce the risks of radiation exposure and might allow a lengthy and more detailed scan.
4. Tightly focused radio waves, perhaps coming from several different angles, could be use to destroy tumors.