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Florida Researchers Create Shortest Light Pulse Ever Recorded

SchrodingerZ writes "Researchers at the University of Central Florida have created the shortest laser pulse ever recorded, lasting only 67 attoseconds. An attosecond is a mere quintillionith of a single second (1/1,000,000,000,000,000,000). The record-breaking project was run by UCF Professor Zenghu Chang, using an extreme ultraviolet laser pulse. '"Dr. Chang's success in making ever-shorter light pulses helps open a new door to a previously hidden world, where we can watch electrons move in atoms and molecules, and follow chemical reactions as they take place," said Michael Johnson, the dean of the UCF College of Sciences and a physicist.' Its hoped that these short laser blasts will pave the way to better understand quantum mechanics in ways we have never before witnessed. In 2008 the previous record was set at 80 attoseconds, the pulse created at the Max Planck Institute in Garching, Germany."

50 of 76 comments (clear)

  1. The width of a virus by hawguy · · Score: 5, Informative

    To put that in perspective, light in a vacuum travels around 20 nm in 67 attoseconds, so the width of the pulse is about the same as the width of the smallest virus or about 1/350th the 7um diameter of a human blood cell.

    1. Re:The width of a virus by Calydor · · Score: 3, Interesting

      Another good comparison relating to how far light travels in that span of time is that it would take TWO of these pulses to cross one 'section' of a 45nm CPU; some of the smallest we currently have in consumer desktops.

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    2. Re:The width of a virus by Fned · · Score: 5, Funny

      Attopeen, you idiot.

      Seriously, how do you fuck that up? HOW do you FUCK THAT UP?!

    3. Re:The width of a virus by snikulin · · Score: 1

      7.90791129 × 10-7 inches!

    4. Re:The width of a virus by gnapster · · Score: 4, Funny

      Oh, give him a break. He only fucked it up a tiny bit.

    5. Re:The width of a virus by deimtee · · Score: 2

      Are you fucking kidding? That's TWELVE orders of magnitude!!

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      I'm guessing that wasn't on their radar screen...
    6. Re:The width of a virus by Guignol · · Score: 2

      it's 13 even, since it was supposed to be 10 times that much ;)

    7. Re:The width of a virus by Hillgiant · · Score: 1

      Yes. But they are very small orders of magnitude.

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  2. Sub-Atomic Strobe Light Party! by AlienSexist · · Score: 1

    Now lets see what these little buggers look like in their own respective slow motion. Careful not to give the quarks any seizures.

    1. Re:Sub-Atomic Strobe Light Party! by dimeglio · · Score: 1

      Hollywood, are you listening?

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      Views expressed do not necessarily reflect those of the author.
  3. Short time, but ... by ackthpt · · Score: 1

    longer than my attention span

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    A feeling of having made the same mistake before: Deja Foobar
    1. Re:Short time, but ... by Zocalo · · Score: 4, Funny

      tl;dr

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  4. How do you even measure this? by Anonymous Coward · · Score: 1

    How do you even measure something of such short duration? Is it an interpolated result?

    1. Re:How do you even measure this? by Mr.CRC · · Score: 4, Informative
  5. Re:Video?!? by CanHasDIY · · Score: 4, Funny

    Can't we get a video?

    There was, but it was only 68 attoseconds long, so you must have missed it.

    --
    An enigma, wrapped in a riddle, shrouded in bacon and cheese
  6. How do they measure this? by PhrostyMcByte · · Score: 3, Interesting

    Can anyone explain how they accurately measure time spans this small? Or did they not measure at all, and instead calculate what it should be from other parameters?

    1. Re:How do they measure this? by BMOC · · Score: 1

      The question is, is the IOC prepared for this kind of accuracy so people can lose an olympic sprint by 12 attoseconds? I'd like to see their anguish.

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      I swear they give me mod points to shut me up.
    2. Re:How do they measure this? by Anonymous Coward · · Score: 5, Informative

      Short version: They use nonlinear optics and variable delay between two beam paths.

      The technique is called Frequency-Resolved Optical Gating (there are a bunch of derived techniques used in specific cases, like the one here), and is actually a brilliant idea when you think about it. You measure the spectrogram of a nonlinear function of the pulse and itself with variable delay.

    3. Re:How do they measure this? by WSOGMM · · Score: 1

      I won't explain it, as I don't feel like reading through all of it right now, but someone else is welcome to! And now it's easy to find.

      Emission of pulse:

      It's actually called Double optical Gating, not Grating, as the article called it. http://www.phys.ksu.edu/personal/chang/Chang-attoweb.pdf

      Detection: Phase Retrieval by Omega Oscillation Filtering

      http://www.creol.ucf.edu/research/publications/2859.pdf

    4. Re:How do they measure this? by stevelinton · · Score: 1

      It is EASY to create the world's shortest laser pulse: emit a single photon. It is monochromatic, coherent (so it meets the laser defninition), and has the shortest possible pulse. .

      No, by cleverly combining multiple photons of different frequencies you can produce a pulse that concentrates its energy in a shorter timespan. Calling it a laser pulse is actually stretching a point a bit, it is triggered by laser light, but the pulse itself is not monochromatic.

    5. Re:How do they measure this? by retchdog · · Score: 1

      ``In addition to creating the light pulse, he created an even faster camera to measure it, which is the Phase Retrieval by Omega Oscillation Filtering (PROOF).''

      --
      "They were pure niggers." – Noam Chomsky
    6. Re:How do they measure this? by The+Master+Control+P · · Score: 4, Interesting

      A monochromatic wave, having zero extent in momentum space, has infinite extent in realspace.

      A laser pulse whose duration is comparable to a single wave period as those in TFA are will in fact have a very broad energy spectrum, which can be understood both through time-energy uncertainty and by noting that a pulse waveform has a broad fourier spectrum, corresponding to broad energy distribution.

      I end up saying or at least thinking this every time a science-breakthrough article comes by on Slashdot: If you think whatever someone did in cutting-edge experimental science is "easy," it's because you don't understand what they did and/or the theory behind it. Think before you speak: If it were actually easy, wouldn't they have already done it this way? Posting a "dumb scientists, that was easy" comment will bring only embarassment.

    7. Re:How do they measure this? by communiss · · Score: 1

      The basic technique involves splitting the pulse into two, sending each pulse down different paths, recombining them in such a way that a third pulse is generated whose strength is proportional to the overlap between the first two pulses. By varying the relative delay between the two pulse replicas, you change the final intensity, and you have mapped the spatial delay onto time delay and effectively measured the pulse. For such short pulses, there are some special tricks that are needed, and a bit of computer reconstruction, but that is the basic physical idea.

    8. Re:How do they measure this? by Cyrano+de+Maniac · · Score: 2

      I think the interesting part of this is that this laser pulse is no longer than approximately 2 wavelengths.

      Wikipedia tells me "extreme ultraviolet" is from 120nm to 10nm. Google tells me "(the speed of light / (10 nm)) * (67 attoseconds)" is 2.0086094686.

      Wow. Just wow.

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      Cyrano de Maniac
    9. Re:How do they measure this? by Crypto+Gnome · · Score: 2

      ``In addition to creating the light pulse, he created an even faster camera to measure it, which is the Phase Retrieval by Omega Oscillation Filtering (PROOF).''

      Apparently when he claimed that it was possible to image a single electron orbiting an atom his supervisor LAUGHED AT HIM and demanded PROOF.

      Insert i-double-dares-ya, scientist-rising-to-a-challenge, whoomp-there-it-is.

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      Visit CryptoGnome in his home.
    10. Re:How do they measure this? by JoeRobe · · Score: 1

      Monochromatic is not a prerequisite for laser light. Coherence and leverage of a population inversion are requirements for it to be laser light, with the latter being sometimes loosely applied. This pulse is as much a laser emission as that from any other, because it is coherent. Laser emission can come from continuous wave lasers (like most red laser pointers), which can be incredibly monochromatic (sub-MHz bandwidth) or from pulsed lasers, which can be incredibly non-monochromatic (many nanometers bandwidth).

      --
      The best way to predict the future is to invent it.
    11. Re:How do they measure this? by Neil+Boekend · · Score: 2

      Unless you're the Doctor.

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      Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
  7. 1/1,000,000,000,000,000,000. What does that mean? by tim_darklighter · · Score: 5, Interesting

    A word to the wise when trying to get people excited about fundmental science: the number "1" followed by a lot of zeroes is meaningless to most people (even scientists). Please give us something to relate that number to and put it in scientific notation!

    67 attoseconds = 6.7 x 10^–18 seconds

    As a photochemist, I know that a femtosecond is (1 x 10^–15 seconds) is the on order of many "fast" chemical reactions, like visible light reacting with your eye, so attoseconds are faster than most chemical bonds breaking/forming.

  8. Re:Video?!? by Razgorov+Prikazka · · Score: 1

    No, but you CAN have sharks with frikkin lasers on their heads zapping you really really fast!

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    rm -rf --no-preserve-root / ...and let /dev/null sort them out...
  9. Re:I can beat that! by ThatsMyNick · · Score: 1

    Are you sure that was a laser pulse?

  10. Re:1/1,000,000,000,000,000,000. What does that mea by hawguy · · Score: 4, Insightful

    A word to the wise when trying to get people excited about fundmental science: the number "1" followed by a lot of zeroes is meaningless to most people (even scientists). Please give us something to relate that number to and put it in scientific notation!

    They did give a unit that scientists can relate to when they said "67 attoseconds". The 1/1,000,000,000,000,000,000 notation is just there for the layman for whom scientific notation means nothing, 1 x 10^-18 means little to most people, but lots of zeros make it clear that it's a very small number.

    67 attoseconds = 6.7 x 10^–18 seconds

    You're off by 10 -- 67 attoseconds = 67 x 10^-18, or 6.7 x 10^-17

  11. Re:1/1,000,000,000,000,000,000. What does that mea by oobayly · · Score: 1

    You're off by a factor of 10 -- 67 attoseconds = 67 x 10^-18, or 6.7 x 10^-17

    I'll get my coat.

  12. Re:Video?!? by Roachie · · Score: 3, Funny

    ...buffering...

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    This sig is not paradoxical or ironic.
  13. Atto-boy!!! by trout007 · · Score: 2

    Great job

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    I love Jesus, except for his foreign policy.
  14. Is there profit in it? by bobs666 · · Score: 1

    Oh I mean can you send and receive data? Say over fiber optic at speeds like this? How about data over a lazar to (where?) say mars?

    I have no problems with basic science, Great science Guys. I am just wondering what is next? the Lab (FAST) is the Florida Atto Science & Technology (FAST). So the tech part is next.

    1. Re:Is there profit in it? by jo_ham · · Score: 3, Insightful

      You can use pump and probe techniques to follow chemical reactions, so while it may not have direct "profit" it will be useful for scientific discovery.

  15. Re:fiber network benefits? by joe_frisch · · Score: 1

    A pulse that short can only be made with UV light (otherwise it would be shorter than a single wavelength). Wouldn't be transmitted by fibers. Its very interesting for science, but no clear application for communications.

  16. Only 2 wavelengths of extreme UV by kipling · · Score: 2

    Even more impressive is that UV radiation is the spectrum from 10 nm to 400 nm, with extreme UV down the 10nm end. So this at most 2 wavelengths.* It barely gets waving.
    * TFA didn't have wavelength data.

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    -- open source? sounds like the real book --
  17. color by dmitrygr · · Score: 1

    How can they speculate about the color of the source (ultra-violet) when a single complete cycle of a wave of that color is 300-400nm long, and the pulse generated here was only 20 nm long?

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    1. Re:color by Anonymous Coward · · Score: 2, Informative

      If you know at what energy levels the photons are released, you know the wavelength.

  18. Re:1/1,000,000,000,000,000,000. What does that mea by tim_darklighter · · Score: 2

    Bah. You got me on 6.7 x 10^-17 sec.

    My gripe is the OP's frame of reference: "an attosecond is 1/1,000,000,000,000,000,000 seconds". That would be like telling me that the Pacific Ocean holds 1,000,000,000,000,000,000 teaspoons of water. That value and that unit should never go together. Lots of zeroes (big or small) is mind-boggling for a layperson or scientist, especially since OP did not give any frame of reference like, "1000 times faster than your eyes turn light into images". It's not a perfect comparison, but it certainly sounds really really fast. (Granted, I should have converted it to furlongs per fortnight.)

  19. Re:1/1,000,000,000,000,000,000. What does that mea by fnj · · Score: 1

    The number is what it is. Sorry if it's not trivial to comprehend the number. That's not the writer/speaker's job. It's the reader/listener's job. It's a fair amount of work to do so, but really not that much. It's character building. I doubt if the brain has to spend more than a tiny fraction of a teaspoon of glucose and maybe a few thimblefuls of oxygen to work out a way to visualize it.

  20. Re:Not fast enough by drkim · · Score: 1

    Three New York Taxis and two bike couriers can get through the intersection during the duration of that light.

    Gedda fuq outta here! New York Taxis and bike couriers don't wait furda frickin' light.

  21. Re:1/1,000,000,000,000,000,000. What does that mea by Neil+Boekend · · Score: 1

    If someone isn't going to understand attoseconds then he can understand that its mindbogglingly short. That's where the 1/1,000,000,000,000,000,000 comes in. If you can understand attoseconds it seems useless information.
    You seem to be in a third group: you can't understand attoseconds, but the 1/1,000,000,000,000,000,000 is to layman-ish for you. You complain because you cannot understand that someone would neither understand attoseconds nor 6.7x10^-17 (of which there are many).
    Now I do agree with complains about only displaying the 1/1,000,000,000,000,000,000 , for that would skip the useful information for scientificly minded people, but that is not an issue here. Attoseconds are used, which are the scientific name.

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    Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
  22. Re:Video?!? by Guignol · · Score: 1

    Awesome, thank you

  23. Re:If it gets to the point... by jellomizer · · Score: 1

    We see God rolling the dice. And we found out that it is a D20. Thats right! Our universe is just one big D&D game. And we just figured out cosmic meta-gaming.

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    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
  24. what about quantum? by ethorad · · Score: 1

    "we can watch electrons move" - I thought quantum dynamics, and Heisenberg's uncertainty principle in particular, prohibits things like that? After all, watching something move essentially means you are able to measure both it's position and velocity?

  25. Re:Video?!? by CanHasDIY · · Score: 3, Funny

    ...buffering...

    Buffering a 68 attosecond video?

    Lemme guess - Comcast?

    --
    An enigma, wrapped in a riddle, shrouded in bacon and cheese
  26. Re:Video?!? by ObiWanKenblowme · · Score: 1

    I don't want to sit through 68 attoseconds of video - is there a tl;dr version?

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    Obvious exits are NORTH, SOUTH, and DENNIS.
  27. Re:1/1,000,000,000,000,000,000. What does that mea by jeffmeden · · Score: 1

    Yes, nothing says "meaningful to most people" like some good old scientific notation... Do you get that 60% of the US doesn't have a college degree, much less multiple degrees, mr. smartass?