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'Optical Fiber' Made Out of Thin Air

Posted by Soulskill on from the sufficiently-advanced-technology dept.

Dave Knott writes: Scientists from the University of Maryland say they have turned thin air into an "optical fiber" that can transmit and amplify light signals without the need for any cables. As described in the research, this was accomplished by generating a laser with its light split into a ring of multiple beams forming a pipe. Very short and powerful pulses from the laser are used to heat the air molecules along the beam extremely quickly. Such rapid heating produces sound waves that take about a microsecond to converge to the center of the pipe, creating a high-density area surrounded by a low-density area left behind in the wake of the laser beams. The lower density region of air surrounding the center of the air waveguide has a lower refractive index, keeping the light focused, and allowing the higher-density region (with its correspondingly higher index of refraction) to act like an optical fiber. The findings, reported in the journal Optica, have applications in long range laser communications, high-resolution topographic mapping, air pollution and climate change research, and could also be used by the military to make laser weapons.

16 of 115 comments (clear)

  1. Perfect to mount by Anonymous Coward · · Score: 5, Funny

    On top of a shark's head.

    1. Re:Perfect to mount by maroberts · · Score: 5, Insightful

      Why is this moderated funny?

      Is this sad, tired old meme actually still genuinely funny in this day and age?

      really?

      Yes.

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      Karma: Chameleon

    2. Re:Perfect to mount by I'm+New+Around+Here · · Score: 2

      As if you've never quoted Monty Python, Star Wars, or Captain Kirk.

      --
      If you think I voted for Trump because of this post, you're wrong. I voted for Dr. Jill Stein of the Green Party. Again.
  2. I read the list of applications by Crashmarik · · Score: 4, Interesting

    and the only ones that looked remotely practical was the laser weapon and remote sensing requiring high power high focus.

    Using lasers for freespac communications is already very practical and well solved, just look at this example

    http://esc.gsfc.nasa.gov/267/2... (BTW definitely one of the better uses of NASA's budget. )

    All the other mentioned applications also have off the shelf solutions that perform exceptionally well. The weapons and high power remote sensing however while listed last seem to have the most to gain. Being able to generate a waveguide in either case solves their two big problems atmospheric distortion and the need to focus large amounts of laser energy on a small point.

    1. Re:I read the list of applications by NatasRevol · · Score: 3, Funny

      Maybe if that squee is out of fear.

      --
      There are two types of people in the world: Those who crave closure
  3. Re:America is Booming on Toads by Russ1642 · · Score: 2

    I see you stopped your music education in kindergarten.

  4. UMD Link by bosef1 · · Score: 4, Informative

    Here's a link to the press release from UMD with some links to the professor's web site.

    http://cmns.umd.edu/news-events/features/2356

  5. What a silly title ... by MondoGordo · · Score: 4, Interesting

    One of the chief benefit of optical fiber is that it doesn't require LOS. All they've done here is demonstrate the capability to mimic the loss-less advantages of optical fiber without actually having a fiber ... once they can do this around corners... then maybe they've "created optical fiber out of thin air" until then not so much.

    1. Re:What a silly title ... by wiggles · · Score: 3, Informative

      Not necessarily - there are lots of situations where it's not practical to run a cable. Secure connectivity between naval vessels is a prime example, others would be for use in the space program, or cheaper data communication between buildings in a campus. Residential broadband internet would be simpler - put an optical transceiver on the roof and point it at a tower - no more digging up the garden to provide fttp.

    2. Re:What a silly title ... by wiggles · · Score: 3, Insightful

      I'm no expert on this technology, but from tfs, it would seem to increase bandwidth by minimizing loss over distance, allowing for longer range and faster speed.

  6. But... by camperdave · · Score: 3, Insightful

    But, does it bend? After all, that's the point behind fiberoptics, to be able to snake a light beam around corners and through tight spaces so that we don't have to maintain perfect optical alignment over a distance. So, what's the point of this setup? Does it keep moths away by burning them on the outer beams?

    --
    When our name is on the back of your car, we're behind you all the way!
    1. Re:But... by gstoddart · · Score: 4, Funny

      Our new Monster Cable Air ionizes the air around the signal ensuring maximal defrobulation of the signal flux and maximal polarization in the near infra-red spectrum, guaranteeing a smooth, minty taste.

      When connect to your tube amplifier, this provides a sound which is spunkier and enhanced in the pink spectrum, causing women to swoon. Achieve smooth bass response like never before.

      For only eleventy zillion dollars, you too can get the most out of your sound system. :-P

      Either this stuff is real, with real benefits, or it's hype. Either way, someone will use it for marketing complete crap.

      --
      Lost at C:>. Found at C.
  7. Pretty well actually by Crashmarik · · Score: 2

    Pretty well actually
    http://www.fastlinks-wireless....
    http://etherealmind.com/free-s...

    They are currently in widespread use

    The real question is just how much improvement would you get with the new system under inclement conditions. The other big question is how they fare against microwave links.

  8. Re:But what does it do? by Anonymous Coward · · Score: 5, Insightful

    air is not transparent and does cause beam scattering. by creating a refractive channel like this they absolutely will reduce beam dispersion. obviously it doesn't eliminate beam spread but even a fiber channel perfectly designed for a single mode will have some diffusion so whats your point?

    they may be able to increase snr by 10^4 over current technologies at 100 m. that's a serious improvement that shouldn't simply be dismissed so thoughtlessly.

  9. Observation at a distance by Scottingham · · Score: 3, Interesting

    This would be good for performing measurements on objects you wouldn't want to get that close to. Like nuclear reactors.

  10. Yawn by tlambert · · Score: 2, Informative

    Predicted the 1960's (Kerr-induced self-focusing: http://journals.aps.org/prl/ab... ), and it was a big part of SDI: http://www.ncbi.nlm.nih.gov/pu... and was again applied to space-to-ground weapons systems in 2009: http://journals.aps.org/prl/ab...

    It was ale demonstrated at LLNL in 2009: http://www.researchgate.net/pu... and 2010: http://www.researchgate.net/pu...

    What's new about this one is that they've renamed the tunnel as the desired artifact, rather than describing it in beams going down the tunnel.