Posted on 12/25/2007 11:45:20 PM PST by neverdem
ScienceDaily (Dec. 24, 2007) — Last year researchers from Duke University stunned the world when they announced a cloaking device for the microwave range. This device made use of metamaterials that had a negative refractive index for electromagnetic radiation. The metamaterials were carefully designed split-ring resonators with a structure size much smaller than the wavelength. Only 10 stacked layers of metamaterials were necessary to achieve the desired invisibility effect.
Now, researchers from the group of Harald Giessen at the University of Stuttgart have succeeded in manufacturing a stacked split-ring metamaterial for the optical wavelength range. This layer-by-layer stacking procedure, which can be repeated as often as desired, is capable of producing well aligned three-dimensional metamaterial structures.
The key to this achievement was a planarization method for the rough nanolithography surface in combination with robust alignment marks which survived the dry etching processes during nanofabrication. This resulted in perfect lateral alignment as well as in perfectly flat layers. The method is suited to produce arbitrary shapes in each layer as well. Thus, more complex structures such as twisted or chiral structures are possible.
The present 3D structures consist of horseshoe-shaped gold nanowires that are arranged in a square pattern and perfectly stacked above each other. Due to the strong vertical coupling, broadband optical features arise. Also, the vertical coupling leads to negative permeability of the structure, which is a prerequisite for a negative refractive index.
Possible applications in the future include perfect lenses that beat the diffraction limit, and optical cloaking devices which provide some invisibility for macroscopic objects.
Na Liu et al., Nature Materials Jan. 2008 issue, Advance Online Publication.
Adapted from materials provided by University of Stuttgart.
Check below the abstract, and you find Research like:
Three-dimensional photonic metamaterials at optical frequencies
1. The overall effect is?
2. The benefit is?
3. The observed effect is?
Thanx
ping
With further development, this material could be used to make its wearer invisible or semi-invisible.
Think invisible torpedo boats slipping into an enemy harbor, invisible airplanes, tanks, APCs, even invisible people when covered with a burqua made of this material.
The effect probably wouldn’t be perfect, but in some applications (Naval) it would be very effective nonetheless.
The Chinese better fork out more cash to Mrs Clinton so they can get this stuff.
Just look for a wake or a 'hole' in the water....especially with a displacement hull.
I can see using it to concel supply caches, fixed positions, and the like.
It would probably be more practical in special forces applications, (infantry), because anything else mobile is going to leave a trail, dust cloud, wake, tracks, or exhaust plume. A foot soldier who could not be seen, especially a very good one, could wreak havoc. (think: the invisible man takes on an airfield...)
Next question, though, is it light enough to add to the combat load these guys carry?
“10 stacked layers of metamaterials” = ten tin layers of very small loop chain mail made of gold. It depends how thin they are able to make the material, but I would guess it could be sewn as a fabric using very thin gold thread/wire.
Probably would be heavy but would be countered by dropping some of the usual combat load and using the material only on special missions. Also gold is expensive, but silver is a possible alternative material.
http://en.wikipedia.org/wiki/Metamaterial
In naval applications, the “hole” would be masked just as well as the ship is. Wake would be a problem, but if you don’t see the ship, you might not notice small wake under low-speed operations or maybe from a hydrofoil.
This is all based on lithography. 40 years ago a lithographer was a guy in a dead-end job in a dying sector of the printing industry. Now...(!)
“Possible applications in the future include perfect lenses that beat the diffraction limit, and optical cloaking devices which provide some invisibility for macroscopic objects.”
http://www.sciencedaily.com/releases/2007/12/071221231539.htm
This had to be stolen from the Klingons... I was wondering when we were going to fess up about stealing their cloaking device...
And the stealth equations had been around for quite a while, too... It may be time to mine old tech for new applications.
Bah!
Was inwented by leetle olt laddy froom Leningrad!
I was thinking more on the order of special forces troops setting explosive charges on enemy aircraft, taking out terrorist strongpoints, etc.—in broad daylight. I wonder if the wearer would cast a shadow?
I’m thinking of the sniper hide from hell!
Depending on the mission, it might be better to slip in, leave 'presents' and go watch the fun from a safe distance.
Possible applications in the future include perfect lenses that beat the diffraction limit...
1. The overall effect is? To make money.
2. The benefit is? Making lots of money.
3. The observed effect is? Makes someone a lot of money.
It was the Romulans that had the cloaking device. We stole it from THEM.
Just a I suspected.
If I understand the defraction limit correctly, this material would allow for the creation of lenses that would be able to “see” objects as small as molecules and possibly even atoms themselves. For macroscopic targets, think high-def telescopes. I’m not entirely sure of this so, anyone? Right? Wrong?
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