• Synthetic Magnetism Used to Control Light: Opens Door to Nanoscale Applications That Use Light Inste
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[quote] [quote] [IMG]http://images.sciencedaily.com/2012/10/121031151609.jpg?1351714582[/IMG] ====================================== Promise of harnessing light. An advance could yield a new class of nanoscale applications that use light instead of electricity. (Credit: © mrage / Fotolia) [/quote] [B]Stanford researchers in physics and engineering have demonstrated a device that produces a synthetic magnetism to exert virtual force on photons similar to the effect of magnets on electrons. The advance could yield a new class of nanoscale applications that use light instead of electricity.[/B] Magnetically speaking, photons are the mavericks of the engineering world. Lacking electrical charge, they are free to run even in the most intense magnetic fields. But all that may soon change. In a paper published in Nature Photonics, an interdisciplinary team from Stanford University reports that it has created a device that tames the flow of photons with synthetic magnetism. The process breaks a key law of physics known as the time-reversal symmetry of light and could yield an entirely new class of devices that use light instead of electricity for applications ranging from accelerators and microscopes to speedier on-chip communications. "This is a fundamentally new way to manipulate light flow. It presents a richness of photon control not seen before," said Shanhui Fan, a professor of electrical engineering at Stanford and senior author of the study. [B]A Departure[/B] The ability to use magnetic fields to redirect electrons is a founding principle of electronics, but a corollary for photons had not previously existed. When an electron approaches a magnetic field, it meets resistance and opts to follow the path of least effort, travelling in circular motion around the field. Similarly, this new device sends photons in a circular motion around the synthetic magnetic field. The Stanford solution capitalizes on recent research into photonic crystals -- materials that can confine and release photons. To fashion their device, the team members created a grid of tiny cavities etched in silicon, forming the photonic crystal. By precisely applying electric current to the grid they can control -- or "harmonically tune," as the researchers say -- the photonic crystal to synthesize magnetism and exert virtual force upon photons. The researchers refer to the synthetic magnetism as an effective magnetic field. The researchers reported that they were able to alter the radius of a photon's trajectory by varying the electrical current applied to the photonic crystal and by manipulating the speed of the photons as they enter the system. This dual mechanism provides a great degree of precision control over the photons' path, allowing the researchers to steer the light wherever they like. [B]Broken Laws[/B] In fashioning their device, the team has broken what is known in physics as the time-reversal symmetry of light. Breaking time-reversal symmetry in essence introduces a charge on the photons that reacts to the effective magnetic field the way an electron would to a real magnetic field. For engineers, it means that a photon travelling forward will have different properties than when it is traveling backward, the researchers said, and this yields promising technical possibilities. "The breaking of time-reversal symmetry is crucial as it opens up novel ways to control light. We can, for instance, completely prevent light from traveling backward to eliminate reflection," said Fan. The new device, therefore, solves at least one major drawback of current photonic systems that use fiber optic cables. Photons tend to reverse course in such systems, causing a form of reflective noise known as backscatter. "Despite their smooth appearance, glass fibers are, photonically speaking, quite rough. This causes a certain amount of backscatter, which degrades performance," said Kejie Fang, a doctoral candidate in the Department of Physics at Stanford and the first author of the study. In essence, once a photon enters the new device it cannot go back. This quality, the researchers believe, will be key to future applications of the technology as it eliminates disorders such as signal loss common to fiber optics and other light-control mechanisms. "Our system is a clear direction toward demonstrating on-chip applications of a new type of light-based communication device that solves a number of existing challenges," said Zongfu Yu, a post-doctoral researcher in Shanhui Fan's lab and co-author of the paper. "We're excited to see where it leads." ====================================== Source: [URL]http://www.sciencedaily.com/releases/2012/10/121031151609.htm[/URL] [/quote] Reminds me of this: [quote] [IMG]http://www.ericzinkann.com/crystals2.jpg[/IMG] [/quote]
I want a sculpture that reflects no light. It'd look like a massive gap in space, like an eerie silhouette that doesn't quite seem corporeal, in a sense.
So, is it we who are going to go with this whole Protoss/Eldar like technology...?
[QUOTE=cccritical;38267218]I want a sculpture that reflects no light. It'd look like a massive gap in space, like an eerie silhouette that doesn't quite seem corporeal, in a sense.[/QUOTE] Not too much of an expert on this, but shouldn't that mean you wouldn't be able to see it at all?
[QUOTE=Adeptus;38267366]Not too much of an expert on this, but shouldn't that mean you wouldn't be able to see it at all?[/QUOTE] Sort of like invisibility, maybe?
I think if that's the case, you can see it. Its just 100% black. Black doesn't reflect any light, but you can still see it if I'm correct, though is there such thing as 100% black?
amazing. This is just incredible.
Does this mean you could pull light in, therefore creating "black" areas where no light can escape?
[QUOTE=Toyokunari;38267444]I think if that's the case, you can see it. Its just 100% black. Black doesn't reflect any light, but you can still see it if I'm correct, though is there such thing as 100% black?[/QUOTE] [media]http://www.youtube.com/watch?v=3tyvvUas6G0[/media]
[QUOTE=cccritical;38267218]I want a sculpture that reflects no light. It'd look like a massive gap in space, like an eerie silhouette that doesn't quite seem corporeal, in a sense.[/QUOTE] There's a name for that It's called "Black"
[QUOTE=Adeptus;38267366]Not too much of an expert on this, but shouldn't that mean you wouldn't be able to see it at all?[/QUOTE] No because just like black holes you know they are there because of the surrounding.
[QUOTE=Adeptus;38267366]Not too much of an expert on this, but shouldn't that mean you wouldn't be able to see it at all?[/QUOTE] It would just be black. That's what black/darkness is; absence of reflected light. You wouldn't see any details in the sculpture, just its silhouette against the non-black background.
[QUOTE=cccritical;38267218]I want a sculpture that reflects no light. It'd look like a massive gap in space, like an eerie silhouette that doesn't quite seem corporeal, in a sense.[/QUOTE] build a long hall way with faint lights on the end and put that on the end. Make it just barely human in shape. do it
[QUOTE=Glorbo;38267570]There's a name for that It's called "Black"[/QUOTE] Black objects still have discernable lines within the outline of the object itself, and depending on the material, might have reflective areas. A totally non-reflective 3D object might just look 'black' the way that we think of it from a fixed perspective, but if you moved around it, it would seem to collapse into itself and distort outwards all at once. Just a thought, doubt something like that could be achieved, but it'd be neat as hell.
[QUOTE=Toyokunari;38267444]I think if that's the case, you can see it. Its just 100% black. Black doesn't reflect any light, but you can still see it if I'm correct, though is there such thing as 100% black?[/QUOTE] A black hole is 100% black, as any light that would be able to reflect it gets absorbed by the intense gravitational pull.
[QUOTE=GlebGuy;38267318]So, is it we who are going to go with this whole Protoss/Eldar like technology...?[/QUOTE] Think we're more following the Tau'ri from stargate, which is another name for the humans of earth. So the stargate program is real...
[QUOTE=cccritical;38267847]Black objects still have discernable lines within the outline of the object itself, and depending on the material, might have reflective areas. A totally non-reflective 3D object might just look 'black' the way that we think of it from a fixed perspective, but if you moved around it, it would seem to collapse into itself and distort outwards all at once. Just a thought, doubt something like that could be achieved, but it'd be neat as hell.[/QUOTE] There are already "blacker than your usual black" materials. Obviously, they never will be "perfectly non-reflective", but I think you could already get some stuff that could get close to what you want. Not sure what exactly would it have to be and how much would it cost, tho. [editline]1st November 2012[/editline] [URL="http://www.wired.com/wiredscience/2009/03/ultrablack/"]Something like this[/URL] [IMG]http://www.wired.com/images_blogs/wiredscience/images/2009/03/31/black.jpg[/IMG] [quote]Scientists have fashioned what may be the blackest material in the universe: a sheet of carbon nanotubes that captures nearly every last photon of every wavelength of light. The substance absorbs between 97 percent and 99 percent of wavelengths that can be directly measured or extrapolated. It’s the closest that scientists have yet come to a black body, a theorized state of perfect absorption whose closest analogue is believed to be the opening of a deep hole. The material, described Monday by Japanese nanotechnologists in the Proceedings of the National Academy of Sciences, is made from a flat array of vertically-aligned, single-walled carbon nanotubes. Photons that aren’t immediately absorbed by a single nanotube deflect off and are absorbed by its neighbors. [/quote] [editline]1st November 2012[/editline] [IMG]http://images.dailytech.com/nimage/7332_darkest-mat_big.jpg[/IMG] Looks pretty black to me.
Couldn't this be used to make true invisibility as well? You make the photons "bend" around the object instead of hitting it.
Christmas tree lights are bad enough when one goes out. Now it's on a nano scale.
[QUOTE=Lord Fear;38272110]Couldn't this be used to make true invisibility as well? You make the photons "bend" around the object instead of hitting it.[/QUOTE] IIRC (and this is just a vague recollection here, I'm probably wrong) that wouldn't make you invisible, it would just make everything affected pitch-black. It'd be good for looking scary and for doing shit at night, but it'd far cheaper to just wear black clothes.
[B]BEND THE UNBENDABLE MAGNETIZE THE UNMAGNETIZEABLE [I]ROW ROW FIGHT DA POWAH[/I][/B] That aside, I want a stealth cloak that much more badly now.
This shit blows my mind
[QUOTE=Cone;38272470]IIRC (and this is just a vague recollection here, I'm probably wrong) that wouldn't make you invisible, it would just make everything affected pitch-black. It'd be good for looking scary and for doing shit at night, but it'd far cheaper to just wear black clothes.[/QUOTE] Nah it would work like genuine invisibility, the only downside would be that anyone using the cloak or machine or whatever wouldn't be able to see anything while it's active unless you generated light inside the field, which would probably nullify the effect since the light would probably pass through the cloak rather easily.
[QUOTE=Cone;38272470]IIRC (and this is just a vague recollection here, I'm probably wrong) that wouldn't make you invisible, it would just make everything affected pitch-black. It'd be good for looking scary and for doing shit at night, but it'd far cheaper to just wear black clothes.[/QUOTE] I would love to become a shadow.
[QUOTE=Pierrewithahat;38272674]Nah it would work like genuine invisibility, the only downside would be that anyone using the cloak or machine or whatever wouldn't be able to see anything while it's active unless you generated light inside the field, which would probably nullify the effect since the light would probably pass through the cloak rather easily.[/QUOTE] Or make it a skintight suit with eye-holes. Floating Eyes!
-snip-
I want a flashlight radiating shadows instead of light
[QUOTE=BloodYScar;38272708]Or make it a skintight suit with eye-holes. Floating Eyes![/QUOTE] Doesn't work like that, we've been experimenting with meta materials that bend light around an object so the light would never hit your eyes so you'd be blind whilst it's active, at least for a particular area of the EM spectrum. We're already testing it on tanks and the MoD have apparently said that it worked flawlessly and there should be actual battlefield applications within a few years. Managed to find a picture of it so here you go: [img]http://mw2.google.com/mw-panoramio/photos/medium/7081236.jpg[/img]
[QUOTE=Toyokunari;38267444]I think if that's the case, you can see it. Its just 100% black. Black doesn't reflect any light, but you can still see it if I'm correct, though is there such thing as 100% black?[/QUOTE] It's like, how much more black could this be? And the answer is... None. None more black.
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