[quote]Materials that bend light in unnatural ways are often touted as the path to futuristic technologies such as cloaking devices and super-powered lenses. But such materials are hard to make, but scientists have now discovered a simpler way using electrons.At Harvard University's School of Engineering and Applied Sciences, a team of researchers led by Hosang Yoon and Donhee Ham showed that using ordinary semiconductors and confining electrons to a two-dimensional plane they could make a material with a so-called negative refractive index that bends radio waves the “wrong” way, and does so a hundred times better than other methods.
A refractive index is a measure of how much a material bends light. An index of 1 means no bending at all. Diamonds have that nice prism effect because they have an index of about 2.42, whereas air bends light hardly at all. Light – and that includes radio waves – bends because as it travels through anything other than a vacuum it slows down. Most materials always have a positive refractive index. That means that if light is approaching a denser, higher-index material from a lower-index one it gets bent to the right if the denser stuff is on that same side.
This all changes if the material has a negative index – as metamaterials do. In that case, the bend would be to the left. An object surrounded by a metamaterial would scatter the light away from it, making it invisible.
The Harvard team’s radio-wave metamaterial itself won't make you invisible, but it could be used to make a kind of "superlens" for radio waves, boosting signals. Or it could divert radar away from a target.
['Invisibility Cloak' Renders Objects Hidden to the Naked Eye]
The researchers set up one micrometer-wide strips of aluminum-gallium-arsenide (a common semiconductor) parallel to each other. They then cooled the device to a few degrees above absolute zero and ran a current through it, while simultaneously applying an electric field to one end.
The electric field accelerates the electrons in one of the strips. Those accelerating electrons couple to those in the strip next to it, and so on. That creates an effect like people in a stadium doing the wave – the electrons don't move but they do couple with others.
This differs from other methods of coupling electrons, which use magnetic fields. In this case, it's an electric field, and the coupling is due to the acceleration of the electrons themselves, a phenomenon called kinetic inductance.
Yoon and Ham then fired a beam of microwaves at frequencies of 1-50 gigahertz at the accelerating electrons. They found that the beam was refracted the "wrong" way, with an index of refraction at up to -700. For comparison, diamond, one of the most refractive materials known for visible light, has an index of 2.42. Most metamaterials developed so far have indexes of between -1 and -5.
Ham told InnovationNewsDaily that the wave of electrons is a key piece of the effect. The electric field applied to the strips creates an effective wave of a specific frequency, so the electrons will refract radio waves in a certain range. But that range can be adjusted by simply raising or lowering the frequency of the field.
This system wouldn't work for visible light, as the semiconductors used aren't transparent. So the technology won’t lead to the creation of invisibility cloaks. But that doesn't mean it won't be possible later on.
Ham said future experiments will look at proving that the apparatus works with higher frequencies, in the terahertz and far infrared range.[/quote]
Source: [URL]http://www.foxnews.com/scitech/2012/08/02/scientists-bend-light-wrong-way/#ixzz22PpIMd3a[/URL]
[quote]So the technology won’t lead to the creation of invisibility cloaks.[/quote]
Fuck
[quote]So the technology won’t lead to the creation of invisibility cloaks.
[/quote]
Boooooooo!
So metamaterials with a negative refractive index can act as signal boosters or radio jammers? Even if it doesn't cloak us, it's still pretty awesome; hopefully it'll mean that signals won't deteriorate so quickly when transmitted into space.
I love science. It's like Lego, half the fun is seeing what incredible things you can create. The other half is seeing how you can break it all in a magnificent way.
That is until we discover the multiple world theory to be real and end up opening a rift to the Space Octopus Zone, at which point everyone gets horribly violated by Hastur.
"wrong" way to bend light?
There is no "wrong way" in science my friend.
[QUOTE=BananaFoam;37053942]"wrong" way to bend light?
There is no "wrong way" in science my friend.[/QUOTE]
Well there is sometimes the "morally wrong way", but that doesn't apply here.
[QUOTE=Drag0nSnak3;37054004]Well there is sometimes the "morally wrong way", but that doesn't apply here.[/QUOTE]
Light should not be bent! Light should be straight, the way God intended it!
Reading through the article, so many references to Primer flow through my head. Are you sure it's not a time machine?
[QUOTE=Doctor Zedacon;37053403]I love science. It's like Lego, half the fun is seeing what incredible things you can create. The other half is seeing how you can break it all in a magnificent way.[/QUOTE]
We, um, we appreciate your enthusiasm, but, well...
I-I don't like the sound of "breaking it all in a magnificent way". I like not being broken! :v:
Fox News? No thanks.
so if they bent it the wrong way do we get visibility cloaks?
[QUOTE=deerinheat;37054618]Fox News? No thanks.[/QUOTE]
there's nothing wrong with this article that i can see though. dont be dumb
[QUOTE=raviool;37055249]so if they bent it the wrong way do we get visibility cloaks?[/QUOTE]
Yes they're called High-Vis jackets.
[QUOTE=Doctor Zedacon;37053403]I love science. It's like Lego, half the fun is seeing what incredible things you can create. The other half is seeing how you can break it all in a magnificent way.[/QUOTE]
and then shuvving it up ur bum to make the winnets dance
[QUOTE=Doctor Zedacon;37053403]I love science. It's like Lego, half the fun is seeing what incredible things you can create. The other half is seeing how you can break it all in a magnificent way.[/QUOTE]
My time playing with lego was divided into thirds, instead of halves, and a 85% slice of that pie was spent searching for that one fucking piece
[QUOTE=TheTalon;37066187]My time playing with lego was divided into thirds, instead of halves, and a 85% slice of that pie was spent searching for that one fucking piece[/QUOTE]
help how do i fractions
Applied sciences, fuck yeah.
[QUOTE=Doctor Zedacon;37053403]I love science. It's like Lego, half the fun is seeing what incredible things you can create. The other half is seeing how you can break it all in a magnificent way.[/QUOTE]
What's stepping on the pieces then, chemical weapons?
[QUOTE=Doctor Zedacon;37053403]I love science. It's like Lego, half the fun is seeing what incredible things you can create. The other half is seeing how you can break it all in a magnificent way.[/QUOTE]
Imagine if it was literally like that...
"Lets put this black hole creator on a shark and see where it leads us to..."
[QUOTE=Sir Whoopsalot;37054072]Light should not be bent! Light should be straight, the way God intended it![/QUOTE]
Refractive pride!
[thumb]http://benallison.com/cms/wp-content/uploads/2012/02/prism-and-refraction-of-light-into-rainbow-2-AJHD.jpeg[/thumb]
[QUOTE=Rents;37068517]What's stepping on the pieces then, chemical weapons?[/QUOTE]
When things go wrong.
Terribly wrong.
To be honest, something like invisibility-cloak is pretty hard to imagine. I mean, you [i]literally[/i] have to let light go THROUGH you, ignoring you completely. Bending light in such a manner seems impossible without 3rd-party help.
This kind of invisablity wont work as it bends light around you therefore you couldnt see because there would be no light entering your eyes :/
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