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Tapering Waveguide Captures a Rainbow
SubComdTaco passes along news of researchers in the US who have trapped a rainbow in a tapering waveguide. The research is described (PDF) on the arXiv. "In 2007, Ortwin Hess of the University of Surrey in Guildford, UK, and colleagues proposed a technique to trap light inside a tapering waveguide [made of metamaterials]... The idea is that as the waveguide tapers, the components of the light are made to stop in turn at ever narrower points. That's because any given component of the light cannot pass through an opening that's smaller than its wavelength. This leads to a 'trapped rainbow.' ... Now Vera Smolyaninova of Towson University in Baltimore, Maryland, and colleagues have used a convex lens to create the tapered waveguide and trap a rainbow of light. They coated one side of a 4.5-mm-diameter lens with a gold film..., and laid the lens — gold-side down — on a flat glass slide which was also coated with film of gold. Viewed side-on, the space between the curved lens and the flat slide was a layer of air that narrowed to zero thickness where the lens touched the slide — essentially a tapered waveguide. When they shone a multi-wavelength laser beam at the... gilded waveguide, a trapped rainbow formed inside. This could be seen as a series of colored rings when the lens was viewed from above with a microscope: the visible light leaked through the thin gold film."
So the bloody leprechaun lied to us !
You need to have two very thin pots of gold first, so you can find the end of the rainbow.
But the ends still technically had gold beneath them.
A bullet may have your name on it but splash damage is addressed "To whom it may concern."
did they try tasting it?
Snowden and Manning are heroes.
now we just have to prove that unicorns exists and put them behind bars.
Suddenly tripping of unicorns and rainbow is not that cool anymore. It is, right?
Dr. Hess was later quoted as saying, "While we're obviously pleased with our success so far, we won't be satisfied until we've trapped not only the rainbow, but the leprechaun and pot of gold as well. Until then, we remain disturbingly dependent on grant money for our research."
>>You need to have two very thin pots of gold first, so you can find the end of the rainbow.
I wonder if you kidnap the scientists they'll grant you three wishes?
Tag: Leprechaun
"If humans could put Rainbows in a Zoo, they would."
--Bill Watterson, via Hobbes in Calvin and Hobbes.
Demented But Determined.
Quantum computers with Optronic pathways are now possible, I wonder how much longer it will be before Asimov's fiction becomes reality...
When the day comes (and it's not to far away) that we can no longer claim to be the most intelligent thing we are aware of will we chose to be slave, master or form a symbiosis?
Just because we create something does not mean that we can claim ownership of it, I wonder if that's why no one has ever seen god?
Sorry, perhaps I am being too dense (ha ha) but if the rainbow disappears when the laser is turned off, they created a rainbow, not trapped it. I see one every time it rains on a oil-slick at a gas station.
Okay, aside from the obvious "nifty" factor, can someone explain in dummy-terms what other cool stuff this might lead to? I realize that research isn't necessarily about making immediately useful things, but surely someone knows of some fantastic avenues this might lead towards?
Not trying to downplay any significance here, just looking for some insight from someone more familiar with what's going on. :)
Their may be a grammatical error, misspeling, or evn a typo in this post.
Soap bubbles are better because I can make them myself, they float around in the air and they look like little gas planets with swirling atmospheres.
Seastead this.
Sounds like an old high school science experiment. Take two microscope slides (flat pieces of glass) lay one on top of another with a thin shim separating them at one end, illuminate this with a monochromatic light and see the fringes. With white light, the peaks for each wavelength would occur at different locations, resulting in a 'rainbow'. Same thing works with soap films, using internal reflection, as the film flows downwards due to gravity and becomes thicker at the bottom (wedge-shaped).
This is also a neat trick for measuring the thickness (or diameter) of a small object. Using it as the shim, count the fringes per centimeter, do some math and you know how thick it is.
Have gnu, will travel.
Selective absorption is a well known effect that takes place whenever a wave propagates in a medium where two boundary conditions have to be fulfilled at once. We observe it regularly in our lab while sending acoustic/elastic waves into a pack of slabs of material. The same thing happens with electromagnetic waves, just like Isaac Newton observed a few centuries ago. Sending the light in a direction parallel to the lenght rather than perpendicular does not discover anything new. Next post, please...
Sounds like an old high school science experiment. Take two microscope slides (flat pieces of glass) lay one on top of another with a thin shim separating them at one end, illuminate this with a monochromatic light and see the fringes. With white light, the peaks for each wavelength would occur at different locations, resulting in a 'rainbow'.
What you're referring to is known as "Newton's Rings":
http://en.wikipedia.org/wiki/Newton's_rings
By crossing this technology with a ballistic projectile... Ohohoh oh Photon Torpedo! Where did I put that patent form...
how come we can see it?
It was a very simple experiment to perform. It doesn't make any measurement of the group velocity or demonstration of trapped light (which would typically involve releasing it controllably and detecting it). The original proposal involved meta-materials to achieve a region with a negative index of refraction to use as the waveguide. They could then (hopefully) manipulate the meta-material to controllably store and retrieve light.
It seems this experiment used a simple meta-material the consisted of the glass surfaces, the 30-nm gold coating and the air gap in a Newton's rings setup. They may even have had the gold coated lens lying around and did the experiment over lunch (which just involved taking a picture). I don't think it's all that interesting until they get storage and retrieval.
So if this is the future...where's my jet pack?
I'd say this is useless unles they've also trapped the gold.
but africans blow the crap out of russians (and japanese)in sports and performance though.
have you thought for a second different genes lead to different strengths.
oh your one of those people that think IQ is everything and strength or stamina are not neccessary
Does the fact that you are a retard make you feel happy?
It's in, well, Towson, which is in Baltimore County, MD.
I'm a consultant - I convert gibberish into cash-flow.
The scientists at Mars Inc have been doing this for years. Further they've even perfected the process of capturing the flavor; in other word, one is able to taste the rainbow. Believe it or not, you can actually find this remarkable technology at your local store.
No, my comment has been "cool-for-saled" ... it's the Rickrolling of 2009.
coolforsale.com Chinese spam scam sweatshop illegal copies half your money back do not buy
While similar in effect to an interference patter type experiment, the actual physics behind the experiment in the article is subtly different. A 'Newtons Rings' type pattern emerges when the distance between the two (partially) reflective surfaces are a certain distance apart, coinciding with an integer value of wavelengths of the light involved. This can can, in theory, be any distance, as long as exact number of wavelengths fit inside. For example, standard interferometers can have distances as large as a centimetre, which is huge compared to the wavelength of visible light.
The effect described is based on the distance between two very reflective surfaces being smaller than the wavelength of light involved, thus preventing the light from travelling further down the waveguide. The taper on the waveguide means that as you go to shorter wavelengths of light, it can travel further, thus generating a 'trapped rainbow' of visible light inside the waveguide.
A key difference to note is that the fringe pattern generated by an interferometer type setup repeats itself as you increase/decrease the distance between the two reflective surfaces, so generating a series of lines or concentric circles. The setup with the 'trapped rainbow' will create a single rainbow pattern.
oh your one of those people that think IQ is everything and strength or stamina are not neccessary
Playing devil's advocate here (the poster you're responding to is a lame troll posting the same crap over and over again, and you're also pretty wrong to say that genetically Africans tend to be great athletes and Westerners are better scientists) - stamina and strength can both be acquired through training, intelligence only in a very limited fashion. So yeah, intelligence is more precious than physical strength.
A good education is a bit like a STD - it makes you unsuitable for a lot of jobs and gives you a desire to spread it.
And then, the rainbows turned on us, the seven frequencies combining their harmonics into a single meta-Frequency
A frequency . . . of DEATH!!!!!
RUN - SAVE YOURSELVES!!!!
An Invisible Entity of Vast Power whose existence must be taken on faith alone: Liberal Media
all this stuff is real? http://www.lawoftime.org/home.html I'm hoping so.