What makes the new materials different from previous metamaterials is that rather than changing two aspects of the way light moves, they change only one. If light is thought of as a wave, the wave front is perpendicular to the direction the light is moving. Imagine an ocean wave crashing ashore: it's moving in just one direction, but the wave front is a huge wall of water. Previous metamaterials changed the direction of light beams passing through them, and the wave front remained perpendicular to the direction of the beam. In the new materials, the light beam changes direction, but the wave fronts don't, giving the impression that they are slipping to the side rather than moving forward. (See image below.)
When a light beam moves through an ordinary material, it moves in the same direction the light waves are facing (top part of image). When a light beam enters a new type of "metamaterial," it changes direction, but the waves remain facing the same way, seeming to slip sideways (see bottom half of image). This image is from a computer simulation. The overall effect on the direction of the light beam is the same as in the earlier metamaterial, but the new materials are simpler to create, and they absorb far less light, making them more attractive for use in optics. The first application the Princeton researchers are developing is a flat lens for chemical-sensing devices, an application for which materials that work with infrared light are particularly well suited. Gmachl says that the current optical setups for such devices are bulky because they use conventional lenses. "The first application would be using that material to miniaturize optical setups" by replacing curved lenses with flat ones, she says. Another early application could be in night-vision devices, which also work with infrared wavelengths. "For people who want to improve night-vision devices, this could be quite interesting," Smolyaninov says. |
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Acoustic Cloak Designed
06/17/2008
Comments
kitk on 10/15/2007 at 1:52 AM
50
GeckoOBac on 10/15/2007 at 7:21 AM
2
But just think about the flat lenses... With metamaterials you can achieve a greater concentration of light than with conventional lenses, thus improving laser technology, astronomic telescopes and any application that needs focused EM waves (maybe even very focused long range radio communications? Or even long distance transfer of power through EM waves? Ok maybe this is a bit to far :P).
You could improve conventional microscopes (if they manage to make metamaterials able to concentrate a large range of very short wavelenght radiations), which would probably remain cheaper than electronic microscopes and more used all around.
About "cloaking" technology, I find a hard time trying to think of something that isn't strictly militarily related, but I guess it could have its uses too.
cjwoodcock on 10/15/2007 at 9:05 AM
1
dmm on 10/15/2007 at 1:07 PM
135
2. Allow police to hide at the side of the road.
3. Fashion. For example, dresses that make fat women look skinny.
4. High-rises in residential areas wouldn't have to be eye-sores.
5. Cloaking clothes for hunters and wildlife photographers (but unfortunately also for criminals and paparrazzi).
6. Cloaked utility poles, cell phone towers, windmills, etc. (only visible up close) would reduce "sight pollution."
7. One word: Toys.
dmm on 10/15/2007 at 1:12 PM
135
2. Wavelength-specific, not broadband.
3. Still rather absorptive.
Nevertheless, cool.
evolvingwheel on 10/16/2007 at 12:57 AM
5
cretin001 on 10/18/2007 at 8:48 PM
35
dmm on 10/22/2007 at 5:36 PM
135
Lots of science has a long lead time before it sees practical applications. For example, Fleming first observed the antibacterial action of Penicillium mold in 1928, but penicillin was not ready for use until 1945. That's a 17-year delay, for something that in retrospect should have been a no-brainer for fast-track development.
Another example is electricity. Faraday demonstrated electromagnetic induction in 1831, but electricity was not put to "practical" use in society until Edison invented the lightbulb and started his electric company. That wasn't until the end of 1880 -- 50 years later. And of course, Faraday's discoveries didn't come out of nowhere. He was building on research into electricity and magnetism that went back at least to Franklin a century before him. So you could make the case that electricity had a 150-year development time, from initial scientific research to first practical application.
A more modern example: general relativity was proposed by Einstein in 1915. It did not see practical use until the GPS system was completed, in 1995. That's an 80-year gap. Another modern example: the structure of DNA was figured out in 1953. The first practical use, DNA testing for genetic defects (or forensics), was not available to the public until about 1983, 30 years later.
In summary, it is unrealistic to expect exciting discoveries to result immediately in consumer applications. There is generally a delay of anywhere from 20 to 100 years. Scientists work for our grandchildren.