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Scientists Trap a Rainbow

Posted by ScuttleMonkey on from the i-can-c-the-light dept.

An anonymous reader writes to tell us that Physicists from both the University of Surrey and Salford University have devised a method to trap a multi-colored rainbow of light inside a prism. "Previous attempts to slow and capture light have involved extremely low or cryogenic temperatures, have been extremely costly, and have only worked with one specific frequency of light at a time. The technique proposed by Professor Hess and Mr Kosmas Tsakmakidis involves the use of negative refractive index metamaterials along with the exploitation of the Goos Hänchen effect, which shows that when light hits an object or an interface between two media it does not immediately bounce back but seems to travel very slightly along that object, or in the case of metamaterials, travels very slightly backwards along the object."

3 of 147 comments (clear)

  1. Scientists Trap a Rainbow by niceone · · Score: 3, Interesting

    Or they don't. They propose a method that might. The meta-materials needed to do this with visible light don't exist yet.

    --
    ccalam - acoustic versions of new songs.
    1. Re:Scientists Trap a Rainbow by Dunbal · · Score: 3, Interesting

      Now they have to think of a way to get the light "out" again. Because after all, what's the point of storing charge in a capacitor's electric field, if you can't get your electrons back when you need them?

      The other interesting thing is - if you don't let the light out, how much light can you put in there? Does it "fill up"? And if it does, what happens when it does? Does the universe end or something?

      --
      Seven puppies were harmed during the making of this post.
    2. Re:Scientists Trap a Rainbow by kebes · · Score: 4, Interesting

      Now they have to think of a way to get the light "out" again. A specific device hasn't been built, but I imagine it would be optoelectronic: that is, they would design the material so that application of an electric field would turn off (or on) the metamaterial effect. If you could switch the capturing capability of the device with an electric current, then obviously you could integrate it into some sort of routing circuitry. In principle one could also design the material to have some unique non-linear optical properties, so that light alone was used to regulate its behavior (e.g. after enough light gets trapped it saturates and releases it), but this kind of "all optical routing/computing" is sorta the "holy grail" of telecom.

      The other interesting thing is - if you don't let the light out, how much light can you put in there? In theory it would build up forever. In reality, any device will be imperfect and probably won't capture light "forever" (but a year or even a minute would be "effectively infinite" for most real-world applications). I imagine that if enough light got "trapped" inside, the resultant EM field in the material would get intense enough to alter the material properties. Eventually the material would break-down, stop being a meta-material, and release the captured light. As I alluded to before, if this were carefully designed it could have some interesting effects (e.g. a "light capacitor" that builds up a big pulse and then releases it all at once).

      In any case, I wouldn't worry about the universe ending!