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Storing Photons In a Solid State Device

Posted by timothy on from the next-year-in-vending-machines dept.

bondisthebest writes in with a report from IEEE Spectrum: "Physicists in Switzerland, led by Nicolas Gisin of the University of Geneva, reported last week in Nature that they have made a solid-state device capable of storing photons for as long as 1 microsecond. The invention will aid in the development of light-based quantum-cryptography networks, which are theoretically impervious to hacking but are currently limited in range to a few dozen kilometers, primarily because of a lack of a suitable way to store the quantum state of photons."

45 of 68 comments (clear)

  1. Photons, Toddlers, and Tonguetwisters by gbulmash · · Score: 4, Funny

    Wow, they've figured out how to store photons for about as long as my three-year-old obeys a command to stop fidgeting.

    From TFA: What they did was "find a way to trap a photon in a collection of 10 million neodymium atoms embedded in an yttrium orthovanadate crystal". Now say that 10 times fast. :-)

    --
    Start a happiness pandemic
    1. Re:Photons, Toddlers, and Tonguetwisters by pope1 · · Score: 1

      Well, it's a start. As soon as they find a way to refresh the state at a regular frequency we'll be able to store (not just transmit) information with light. I hope it involves the use of tiny, tiny mirrors. =P

      --
      /* * pope1 */
    2. Re:Photons, Toddlers, and Tonguetwisters by edsousa · · Score: 1

      You win nothing. He said "10 times faster" not say it 10 times.

    3. Re:Photons, Toddlers, and Tonguetwisters by Anonymous Coward · · Score: 1, Insightful

      1 microsecond of persistence...they'd need to be refreshed at a rate of 1GHz, which seems plausible.

      After reading the article, it seems we're still a long long long way off from any kind of general-purpose photonic processor, but this seems like a very important advance.

    4. Re:Photons, Toddlers, and Tonguetwisters by Dutch+Gun · · Score: 5, Interesting

      I'll bet if you also chill your 3 year old to near absolute zero, you can get him to stop fidgeting for much longer than that.

      Anyhow... *cough*, I had to follow an extra link to see what this might be good for. Apparently, one could theoretically build a quantum repeater, required for quantum networks, which supposedly would be impervious to hacking, because supposedly one can't read the quantum data without actually changing it's state to some degree.

      But then there's this:

      Quantum repeaters will be an essential component for long-range quantum information networks because photons degenerate--their quantum state changes--as they travel and need to be regenerated periodically in a way that preserves their original information. No one has been able to make a reliable quantum repeater yet. One of the prerequisites for such a device is a quantum memory that can store photons (and their quantum state) without destroying entanglement. Entanglement, a property important to quantum networks, allows two photons to be linked in such a way that, if someone measures one of the photons, the quantum state of the other becomes known as well. When a photon travels through optical fiber, entanglement degeneration occurs by approximately 300 kilometers.

      So, if they could somehow figure out how to build a repeater, doesn't that by definition mean they could read the data, then recreate and retransmit it? Or is the act of repeating and retransmitting the quantum data different than "reading" the data? I don't quite understand how this is supposed to work (not too surprising, I'm not a physicist). Can anyone explain this supposed paradox to me?

      --
      Irony: Agile development has too much intertia to be abandoned now.
    5. Re:Photons, Toddlers, and Tonguetwisters by SinGunner · · Score: 1

      Old joke-answer:

      that
      that
      that
      that
      that
      that
      that
      that
      that
      that

    6. Re:Photons, Toddlers, and Tonguetwisters by SmlFreshwaterBuffalo · · Score: 4, Interesting

      I think "reading" is referring to actually retrieving something of value from the data. If retransmitting requires some sort of processing to occur, then the processor would have to read the data in order to retransmit it. But if retransmitting can be done at the quantum level (the goal of this as far as I can tell), then there is nothing actually reading the data, it's merely propagated through.

      A (rather bad) analogy would be if someone were to speak to you in a language you do not know, and you repeated the words (data) verbatim. You retransmitted the words, but did not need to process them (i.e. read the data). That is, you didn't need to know what the words meant to repeat them.

    7. Re:Photons, Toddlers, and Tonguetwisters by ArsonSmith · · Score: 1

      He said fast

      thatthatthatthatthatthatthatthatthatthat

      --
      Paying taxes to buy civilization is like paying a hooker to buy love.
    8. Re:Photons, Toddlers, and Tonguetwisters by mortonda · · Score: 1

      Depends on the order of operations, parens would make it more clear:

      Say (that 10 times) fast

      that10times

    9. Re:Photons, Toddlers, and Tonguetwisters by davidsyes · · Score: 1

      When you store those "photons" in your solid state device, you KNOW when your child first becomes the twinkle in your eye...

      --
      Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
    10. Re:Photons, Toddlers, and Tonguetwisters by thelamecamel · · Score: 1

      There usually are a few touted applications of "slow light".

      As a pulse/beam of light slows down, it intensifies (just like chairs on a chairlift bunch up at the slow top and bottom base stations). As the intensity of the light goes up, so do the nonlinear effects of the medium, so if you want to exploit nonlinearity, slow light is a good thing. However, this particular implementation (requiring neodymium atoms as the medium) won't be useful for this application because I don't think many people are interested in the nonlinearities of that medium

      The other big application of "slow light" is relevant here - it is an optical buffer, a delay line that you can send light into. If you want to build an optical router (a challenging goal), then you need to be able to delay individual packets to avoid packet collisions. Now that slow light is supposedly sorted, you just need to get to work on the optical logic required for routing, which according to some big names, can physically never beat electronics as long as TCP/IP is still around.

    11. Re:Photons, Toddlers, and Tonguetwisters by b4upoo · · Score: 1

      Is this sort of like finding a way to make memory expensive again? Yeh, I know P.C. Magazine will soon explain why every home PC needs this technology.

    12. Re:Photons, Toddlers, and Tonguetwisters by b4upoo · · Score: 1

      So will this tech be able to build a stronger chess computer? Will I ever be able to win?

    13. Re:Photons, Toddlers, and Tonguetwisters by Dutch+Gun · · Score: 1

      I think "reading" is referring to actually retrieving something of value from the data. If retransmitting requires some sort of processing to occur, then the processor would have to read the data in order to retransmit it. But if retransmitting can be done at the quantum level (the goal of this as far as I can tell), then there is nothing actually reading the data, it's merely propagated through.

      A (rather bad) analogy would be if someone were to speak to you in a language you do not know, and you repeated the words (data) verbatim. You retransmitted the words, but did not need to process them (i.e. read the data). That is, you didn't need to know what the words meant to repeat them.

      Thanks for the clarification. That makes a bit more sense.

      --
      Irony: Agile development has too much intertia to be abandoned now.
    14. Re:Photons, Toddlers, and Tonguetwisters by Dutch+Gun · · Score: 2, Interesting

      So will this tech be able to build a stronger chess computer? Will I ever be able to win?

      Forget chess. We've already beaten grandmasters with computers. The next AI challenge is programming a decent Go player.

      --
      Irony: Agile development has too much intertia to be abandoned now.
    15. Re:Photons, Toddlers, and Tonguetwisters by ScrewMaster · · Score: 1

      So will this tech be able to build a stronger chess computer? Will I ever be able to win?

      Forget chess. We've already beaten grandmasters with computers. The next AI challenge is programming a decent Go player.

      And then after that will be making computers behave like they do in movies.

      --
      The higher the technology, the sharper that two-edged sword.
    16. Re:Photons, Toddlers, and Tonguetwisters by lgw · · Score: 1

      we'll be able to store (not just transmit) information with light

      That basic idea is hardly new. I'm not sure why you'd want to store information as light, but storage vs transmission is a blurry distinction these days in any case. A modern undersea cable "stores" megabits as light.

      --
      Socialism: a lie told by totalitarians and believed by fools.
    17. Re:Photons, Toddlers, and Tonguetwisters by RiotingPacifist · · Score: 1

      So if im not a vet, and i cant tell if the cat is asleep or dead, it is in a state of both sleep and dead until i take it to the vet.

      --
      IranAir Flight 655 never forget!
  2. Schrödinger called... by Anonymous Coward · · Score: 5, Funny

    ...he said your server was either hacked or it wasn't.

  3. I'm Gonna Be Rich! by CopaceticOpus · · Score: 5, Funny

    I just need to be the first to patent two mirrors facing each other...

    1. Re:I'm Gonna Be Rich! by Kabuthunk · · Score: 3, Insightful

      Course, then you're left with the problem of getting the photon to STAY between the mirrors, instead of just go back and forth away from the source until it hits the bottom of the mirror.

      You'd have to find a way to release the photon exactly perpendicular to the mirror, but not have the emitter get in the way when it bounces back.

      --
      Planet Zebeth - Metroid with a twist
    2. Re:I'm Gonna Be Rich! by ArsonSmith · · Score: 3, Funny

      Here's my initial design blue prints:

      Active Photon Refection and Recapture Matrix

      --
      Paying taxes to buy civilization is like paying a hooker to buy love.
    3. Re:I'm Gonna Be Rich! by philspear · · Score: 1

      You're behind the curve when it comes to patent law. Some guy patented mirrors last week. Someone tried to present evidence of prior art, but the judge just saw himself.

    4. Re:I'm Gonna Be Rich! by gbulmash · · Score: 1

      I just need to be the first to patent two mirrors facing each other...

      Just don't get a witch between them (read Terry Pratchett's "Witches Abroad" if you don't understand).

      --
      Start a happiness pandemic
    5. Re:I'm Gonna Be Rich! by Veggiesama · · Score: 1

      I used to be obsessed with this idea when I was a kid (I was a very strange kid). Except not photons, but a beam of light. How can I trap it between mirrors?

      My final idea was to shine a beam of light in a box or sphere of mirrors, figure out a trajectory to keep the light from shining back out my hole for like a second, then shut the lid really quick (which has a mirror to block the escaping light).

      Why couldn't someone have just explained to me the simpler way of solving this problem?

      I.e., go outside and do something productive.

    6. Re:I'm Gonna Be Rich! by ScrewMaster · · Score: 1

      Oh yeah, and reverse the phase and amplify by one to the fourth.

      And then use a verteron pulse to regenerate the waveform at fixed intervals.

      --
      The higher the technology, the sharper that two-edged sword.
    7. Re:I'm Gonna Be Rich! by Justin+Hopewell · · Score: 1

      I always wanted to do something like this, also, but, you know, since I can't move my hands at the speed of light (to close the box) it was just a curiousity.

    8. Re:I'm Gonna Be Rich! by Hucko · · Score: 1

      I did something similar (made a cube of mirrors) but couldnt figure how to observe the light without letting it out.

      --
      Semi-automatic amateur armchair Australian philosopher; conjecture ready at any moment...
  4. impervious shivurvious by moniker127 · · Score: 1

    impervious to hacking. Ba ha ha. Why do they bother with these descriptions? They know they will just be emberassing themselves later.

    1. Re:impervious shivurvious by mark-t · · Score: 3, Interesting

      Sure, if somebody finds a way to hack the physical universe in which we live and change its laws of operation, I suppose its possible.

      Quantum cryptography is secure by virtue of actual physical laws. Unless we are all living in the Matrix or some weird-ass crap like that, I'd say it's a pretty safe bet that it's secure. Even the mere _attempt_ to hack it would be immediately obvious to both the sender and the receiver.

      --
      File under 'M' for 'Manic ranting'
    2. Re:impervious shivurvious by poopdeville · · Score: 1

      Quantum cryptography is secure by virtue of actual physical laws. Unless we are all living in the Matrix or some weird-ass crap like that, I'd say it's a pretty safe bet that it's secure.

      Even if we were in the Matrix, it would still be secure. Yes, "the machine" could change physical laws (conceivably), but the machine already runs your life. So it doesn't matter if it sees your dumb bank code. Replace "the machine" with "God" if you are so inclined. Unless the machine/God-figure decides to reveal your secrets, nobody will see them.

      Information security is about access to information. So is epistemology. Who knew!

      --
      After all, I am strangely colored.
    3. Re:impervious shivurvious by b4upoo · · Score: 1

      Well, God did create all universes as a binary program but then Microsoft patented all possible combinations of binary code. That leaves us in doubt as to whom is actually running the bits.

    4. Re:impervious shivurvious by Veggiesama · · Score: 1

      That leaves us in doubt as to whom is actually running the bits.

      Well I don't know about the bits, but I sure know about the bytes. The bites. The strings. You know, string theory. That is, the spaghetti strings. That you bite. They also fly, kind of like a flying monster.

      It sounded funnier in my head.

    5. Re:impervious shivurvious by rubycodez · · Score: 1

      that's assuming the model we call quantum mechanics is actually accurate. maybe it's merely useful for now.

    6. Re:impervious shivurvious by Hucko · · Score: 1

      Yes, that is why I have taken to not speaking...

      err... ditto?

      --
      Semi-automatic amateur armchair Australian philosopher; conjecture ready at any moment...
  5. Just get a small black hole by Baruch+Atta · · Score: 2, Insightful

    Easy. Just get a small black hole. Shoot the photons around the gravity well. They'll last almost forever.

    --
    You can only be young once. But you can always be immature.
    1. Re:Just get a small black hole by osu-neko · · Score: 2, Funny

      Easy. Just get a small black hole. Shoot the photons around the gravity well. They'll last almost forever.

      No problem, we should have the LHC back online this year. :)

      --
      "Convictions are more dangerous enemies of truth than lies."
  6. Why not use it for by Whiteox · · Score: 2, Insightful

    Fast Ram?
    Sounds ideal.
    In fact I may just go and RTFA.

    --
    Don't be apathetic. Procrastinate!
  7. OMG by indigoid · · Score: 1

    It's full of stars!

    --
    P-plate adventurer
  8. Re:Slow glass? by ScrewMaster · · Score: 1

    Yes, I do. Those were interesting stories, actually. It's been many years since I read them.

    --
    The higher the technology, the sharper that two-edged sword.
  9. Re:Slow glass? by ScrewMaster · · Score: 1

    Anyone remember the 'slow glass' in stories by Robert Shaw.

    For anyone who's interested, here's one of them

    --
    The higher the technology, the sharper that two-edged sword.
  10. What's the big deal? by WhiteHorse-The+Origi · · Score: 1

    I can store a photon for several seconds by sending it through a medium in which the speed of light is different from the speed in the original medium. Maybe I should patent all known mediums that light can travel through as potential storage devices for photons.

    1. Re:What's the big deal? by Whiteox · · Score: 1

      I can't think of why that won't work, but I'm not a physicist.
      You can extend that model a bit. If you had a series of fast-slow-fast-slow-fast media then why is the light still traveling fast at the end of the chain? What happens to entropy? A loss of velocity must mean a generation of energy somehow. The only thing I can think of is that you won't be getting as many photons out as was going in.

      Can a physicist explain this?
      If Einstein's Theory is correct, that if you accelerate mass to the speed of light, it turns into energy, but if you slow light down it doesn't turn into mass?

      --
      Don't be apathetic. Procrastinate!
    2. Re:What's the big deal? by WhiteHorse-The+Origi · · Score: 1

      Actually I can explain: E=h*c/lambda is the energy equation for a photon. If c changes, which is the case here, the wavelength(lambda) would shift accordingly and there would be no loss of energy. There might be some energy lost at the interface between 2 mediums, but not usually if it's set up correctly.

  11. A Lightnin' Jar! by A+New+Normalcy · · Score: 1

    end

    --
    ...Lorenzo / I'm into kinky crustaceans. I just discovered internet praWn.