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Japanese Scientists Fire the Most Powerful Laser On the Planet

Posted by samzenpus on from the amazing-laser dept.

Sepa Blackforesta writes: Scientist from University of Osaka claim have fired the world's most powerful laser. The beam was intact for 2-petawatt, pulse lasted just one picosecond. While it produced a huge amount of power, the energy required for the beam itself is equivalent to that needed to power a microwave for two seconds. An associate professor of electrical engineering at Osaka University Junji Kawanaka says “With heated competition in the world to improve the performance of lasers, our goal now is to increase our output to 10 petawatts.”

77 of 117 comments (clear)

  1. disappointing by Thisstatementisfalse · · Score: 1

    It only lasted for a picosecond...

    1. Re:disappointing by Anonymous Coward · · Score: 5, Funny

      It only lasted for a picosecond...

      Longer than I usually do.

    2. Re:disappointing by ShanghaiBill · · Score: 5, Informative

      It only lasted for a picosecond...

      A petawatt for a picosecond is one kilojoule. That is enough energy to warm a liter of water by 0.24C.

    3. Re:disappointing by Noah+Haders · · Score: 1

      following this thought, most microwaves are 1200W, so to power one for ten seconds is 12kJ. so it's not unreasonable if the energy efficiency of their setup is 10% that the statement about microwave ovens is correct.

    4. Re:disappointing by crimson+tsunami · · Score: 1

      I didn't read the article, but the summary says 2 seconds not 10.

    5. Re:disappointing by maz2331 · · Score: 1

      Or ablate the surface of a small fuel pellet and cause it to implode. Inertial confinement fusion is all about super intense and short-duration shots of energy.

    6. Re:disappointing by Deep+Esophagus · · Score: 1

      With heated competition in the world to improve the performance of lasers...

      I see what he did there.

    7. Re:disappointing by Aaron+B+Lingwood · · Score: 1

      Sometimes, I love the mods.

      --
      [Rent This Space]
    8. Re:disappointing by infolation · · Score: 1

      They're smoking the competition.

      arf arf

    9. Re:disappointing by mangansie · · Score: 1

      It only lasted for a picosecond...

      A petawatt for a picosecond is one kilojoule. That is enough energy to warm a liter of water by 0.24C.

      Now I finally know what I need to replace my broken kettle with....

    10. Re:disappointing by arglebargle_xiv · · Score: 4, Funny

      It only lasted for a picosecond...

      They couldn't risk cooking the shark it was attached to.

    11. Re:disappointing by Big+Hairy+Ian · · Score: 1

      The important piece of information that's missing is how powerful was the microwave they compared it to?

      --

      Build a Man a Fire, and He'll Be Warm for a Day. Set a Man on Fire, and He'll Be Warm for the Rest of His Life.

    12. Re:disappointing by jellomizer · · Score: 1

      Still if it lasted for 420 Picoseconds (still less than a blink of an eye) it would bring a liter of ice to boiling. Most likely to vapor in under a second.
       

      --
      If something is so important that you feel the need to post it on the internet... It probably isn't that important.
    13. Re:disappointing by Muad'Dave · · Score: 1

      Two petawatts for a picosecond is an average power of 2000W. That's about 2 secs for an average microwave, taking inefficiency into account.

      --
      Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
    14. Re:disappointing by Khyber · · Score: 1

      "That's about 2 secs for an average microwave"

      Most average microwaves are 800-1200W. 2000w is getting into industrial/commercial-level microwaves.

      --
      Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
    15. Re:disappointing by Muad'Dave · · Score: 1

      Here's one that claims 1460 W, so it's not _too_ far off base (look at the specs page).

      I said "That's about 2 secs for an average microwave" meaning 2 secs x 1000 W is 2000 W-secs. I mixed up my units, I know.

      --
      Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
    16. Re:disappointing by Flavianoep · · Score: 1

      Regardless, the real question is how do we strap these things to a shark's head.

      It's can't just 'strap' a laser weapon to a shark's head because of the constraints Newtonian Physics and Euclidean Geometry. However, you can achieve something like that with some workarounds from Quantum Mechanics. <|:-)

      --
      Linux is for people who don't mind RTFM.
    17. Re:disappointing by Coren22 · · Score: 1

      12/5 = 2.4 kJ, so it is still in the range, that would be a little less than 50% efficiency (as ShanghaiBill stated above).

      --
      APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
    18. Re:disappointing by oldmac31310 · · Score: 1

      Four football fields.

      --
      http://www.acetonestudio.com
    19. Re:disappointing by Lehk228 · · Score: 1

      or enough to flash boil 2 ml of ice water in a picosecond

      --
      Snowden and Manning are heroes.
  2. Why does anyone care? by quenda · · Score: 2

    Why should anyone care about the power level, as opposed to the pulse energy?
    ie why does it matter if the kilojoule is spread over one or ten picoseconds? Without this vital piece of information, it is hard to get excited (pardon the pun).

    1. Re:Why does anyone care? by Noah+Haders · · Score: 5, Informative

      Why should anyone care about the power level, as opposed to the pulse energy?

      people who have tattoos should care, for one. the ideal tattoo removal laser has really high instantaneous power but really short pulses. this way you get high power but low energy per pulse.

      the tattoo ink breaks down better with higher power lasers because it breaks the bonds holding the ink molecules together. but by keeping the energy per pulse low, you're minimizing the tissue damage since tissue damage grows with the amount of energy absorbed by the skin. when you break up the ink molecules into smaller pieces then the immune system can flush away the bits into your lymph nodes. tattoo is gone!

    2. Re:Why does anyone care? by quenda · · Score: 1

      But does one vs ten picosecond matter?
      And I'm pretty sure you do not want a laser of this size pointed at your arm, unless you are looking for instant amputation.

    3. Re:Why does anyone care? by Michael+Woodhams · · Score: 2

      You can use high powered lasers in short pulses to compress and heat a fuel pellet to achieve fusion. A particular approach called fast ignition requires a petawatt pulse. Given that the laser is named LFEX for "Laser for Fast Ignition Experiments", it is a good bet this is what it is for.

      (My expertise in this is limited to having had an inkling which Wikipedia article to look in for the answer. Further input from real experts is welcome.)

      --
      Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
    4. Re:Why does anyone care? by Anonymous Coward · · Score: 5, Interesting

      Timewise, atomic/molecular physics spans many orders of magnitude (from metastable states with lifetimes measured in hours, to inner-shell Auger processes with lifetimes measured in femtoseconds).

      However making short pulses isn't the true goal of lasers like this (A Q-switched laser that fits on a coffee table can make femtosecond pulses). The true thing of interest is the *number density of photons*. Since it's a laser, the photons have the same energy. Then the total number of photons is proportional to the energy in the pulse, but the *number density* - N/V - scales as the inverse of the spot size and the inverse of the duration (since duration = length / c).

      Therefore, the smaller the spot size and the shorter the pulse, the higher the number density of photons that is acheived in a given energy.

      When you have a high enough number density, nonlinear things (whose rate of occurrence is the number density of photons raised to the order of the nonlinearity) happen and nonlinear things are Generally Interesting. For example, a sufficiently high laser power is capable of literally blowing protons/neutrons out of an atomic nucleus - IF you can dump roughly a nucleon binding energy into an area the size of a nucleus, in less than the time it will try to radiate it away.

    5. Re:Why does anyone care? by whoever57 · · Score: 2

      You can use high powered lasers in short pulses to compress and heat a fuel pellet to achieve fusion. A particular approach called fast ignition requires a petawatt pulse

      I think that should be "a very short pulse" -- but pulses used for ignition are much higher energy -- from 70kJ to 2MJ, according to your link.

      I would not believe anything in the article, though, since the writer seems to have a very poor grasp of basic physics:

      Two quadrillion wattsit self is a massive amount of output. The burst only lasted about one picosecond (1/1,000,000,000,000 of a second), so while the energy output was incredibly large, the actual amount of power (energy divided by time) the LFEX used wasnâ(TM)t all that big. When it was all said and done, the laser only produced enough power to run a microwave for about two seconds.

      --
      The real "Libtards" are the Libertarians!
    6. Re:Why does anyone care? by Anonymous Coward · · Score: 1

      Higher instantaneous power leads to higher incidence of nonlinear effects. For example, if the power is high enough, there is so much photon density that two photons of some wavelength can appear as a single photon of half the wavelength to a molecule. This is used in two-photon microscopy, which will excite only a tiny region of a specimen to fluoresce and light up, giving much sharper images.

    7. Re:Why does anyone care? by umafuckit · · Score: 5, Informative

      I don't know about those times scales, but femto-second pulsed lasers are damn useful for imaging. Briefly, say the experimenter images green fluorescence. Normally, to get green fluorescence you need to excite with blue light of, say, 450 nm. However, if you can pack enough photons into a short packet then you can also get green fluorescence at about double the wavelength. It's called "two photon absorption" and won a Nobel prize. So you pump in 900 nm light and get back green. The advantage is that longer wavelengths are scattered less by biological tissue and, crucially, the depth of field is much better so there is very little out of focus emitted green light (see image in link). Because the laser scans over the specimen relatively slowly (e.g. a few times a second), you can collect scattered green photons and still assign them back to where they came from. So it's very efficient. Maybe this new laser will all for the process to work efficiently with 3 or even 4 photons.

      --
      soylentnews.org
    8. Re:Why does anyone care? by EmperorArthur · · Score: 1

      Why should anyone care about the power level, as opposed to the pulse energy?
      ie why does it matter if the kilojoule is spread over one or ten picoseconds? Without this vital piece of information, it is hard to get excited (pardon the pun).

      Well, given that a 9mm has about the same energy as two or three punches... Yeah, I'd say the time and method of energy transfer/release is extremely important.

      Sources:
      https://en.wikipedia.org/wiki/...
      http://www.science.ca/askascie...

      --
      So lets pretend that we've just completed writing this code, as opposed to having just completed sabotaging it -Altera
    9. Re:Why does anyone care? by r0kk3rz · · Score: 1

      Why should anyone care about the power level, as opposed to the pulse energy? ie why does it matter if the kilojoule is spread over one or ten picoseconds?

      I imagine this type of laser technology would be useful for Inertial Confinement Fusion based projects.

    10. Re:Why does anyone care? by r0kk3rz · · Score: 1

      I think that should be "a very short pulse" -- but pulses used for ignition are much higher energy -- from 70kJ to 2MJ, according to your link.

      The HiPER is a proposed project to experiment with this type of fusion, requiring the use of Petawatt scale lasers

      A 2 Petawatt pulse over 1 Picosecond isn't quite a 4 Petawatt pulse over 10 Picoseconds, but its on its way. Considering the organisation in TFA are now planning on scaling to produce 10 Petawatt pulse, maybe the timescale can be reduced for Ignition.

    11. Re:Why does anyone care? by towermac · · Score: 1

      I don't think you would have felt it.

      Maybe. But it's not even close to being able to hurt you.

    12. Re:Why does anyone care? by drolli · · Score: 1

      * Because destruction free techniques like laser ablation are base on high local fields

      * because a 1ps pulse spreads over 10^12 Hz bandwidth, which may be useful if you want to have "more white" light (but this pulse is actually not very short)

      * because pump-probe techniques depend on short pulses. If you additionally need a strong pulse, higher power may come in handy

      * I also imagine it could be an advantage for generating plasma.

    13. Re:Why does anyone care? by Billy+the+Mountain · · Score: 1

      Well yeah, but it will probably make your arm radioactive. Plasma Acceleration

      --
      That was the turning point of my life--I went from negative zero to positive zero.
    14. Re:Why does anyone care? by Tough+Love · · Score: 1

      Why should anyone care about the power level, as opposed to the pulse energy?

      Thresholds, the same reason that the Large Hadron Collider may break apart subatomic particles while a 16 inch cannon cannot, even though the cannon delivers more total energy.

      --
      When all you have is a hammer, every problem starts to look like a thumb.
  3. What would you use that for? by R3d+M3rcury · · Score: 1

    Making enormous swiss cheese!

  4. Analogies? by marciot · · Score: 4, Funny

    Help me understand. Is a two petawatt laser being fired for a picosecond more like being sneezed on by a rhino with a cold or more like being shat on by an elephant with a bad case of explosive diarrhea?

    1. Re:Analogies? by Noah+Haders · · Score: 1

      it's like being electrocuted while fixing your lamp for one second.

    2. Re:Analogies? by Bob+the+Super+Hamste · · Score: 1

      About 1/2 the energy of a .30-06 round. So likely closer to elephant with a bad case of explosive diarrhea but after consuming mostly Mexican food first.

      --
      Time to offend someone
    3. Re:Analogies? by Timoleon · · Score: 1

      Attention People of Tokyo!!!!!!!

  5. .55wh or 2kJ by thinkwaitfast · · Score: 1

    --
    Filter error: You can type more than that for your comment

  6. What? by slashmydots · · Score: 1

    Why would they need a laser to do this? It's like 3000 watt-seconds. That means the total dissipated energy used for, for example cutting a piece of metal, would be measured in energy used over time. In other words, that laser wouldn't cut a damn thing.

    1. Re:What? by wbr1 · · Score: 1
      Lasers are not just used for cutting you insensitive clod.

      For instance, they can be attached to sharks instead.

      I came into this thread looking for sharks. I was disappointed and decided to remedy the situation.

      --
      Silence is a state of mime.
  7. On the planet? by physicsphairy · · Score: 1, Redundant

    Which planet? Alderaan?

    --
    When things get complex, multiply by the complex conjugate.
  8. If I only worked for 1 picosecond... by SlithyMagister · · Score: 5, Funny

    I'd get fired too

    1. Re:If I only worked for 1 picosecond... by _merlin · · Score: 1

      Yeah, I was reading it as though the object would be a job title, as in "Japanese Scientists Fire the Most Powerful CEO On the Planet". Now that would be a real achievement.

  9. Godzilla? by DrNico · · Score: 1, Redundant

    Is nobody going to mention Godzilla?

    1. Re:Godzilla? by TimSSG · · Score: 1

      Is nobody going to mention Godzilla?

      I was going to ask how large does the shark have to be to have this laser mounted on it. But, maybe Godzilla would be a better Lazar platform. Tim S.

    2. Re:Godzilla? by Billy+the+Mountain · · Score: 1

      Thanks, I'll keep that on my R.A.D.A.R.

      --
      That was the turning point of my life--I went from negative zero to positive zero.
  10. The next step... by turbinicarpus · · Score: 3, Funny

    "We are currently working on mounting this laser on a giant robot," added Professor Kawanaka.

  11. Re:What? Math fail... by Fallen+Kell · · Score: 1

    It is more like 2000 watt/seconds. Last I checked 2 petawatts / 1 picosecond will give you a 2 as the most significant digit...

    --
    We were all warned a long time ago that MS products sucked, remember the Magic 8 Ball said, "Outlook not so good"
  12. I know what they need it for by Required+Snark · · Score: 1

    Shark bait.

    --
    Why is Snark Required?
    1. Re:I know what they need it for by Bengie · · Score: 1

      shark bait hoo haha - Finding Nemo

  13. Executing in an invalid environment! by ASDFnz · · Score: 1

    Clicked in the link and got;-

    Executing in an invalid environment for the supplied user

    Does that mean they lasered the webserver for me?

    1. Re:Executing in an invalid environment! by cfalcon · · Score: 1

      It means you either supplied an invalid user for the environmental execution in question, or you supplied an invalid user for the execution environment. You should see to that. I hear there is a pill.

  14. Re:God damn it... by Fusselwurm · · Score: 1

    it's LASER as long as you pronounce it "ell ey ess ee ar". What, you dont? Then why dont you stop nitpicking, and just accept that at some point, a pronouneable acronym becomes a new word.

  15. two microwaves, you say? by ihtoit · · Score: 1

    Would they be Class C, Class D? Be specific, I'm trying to figure out how long a Cree would last connected in series to a three bar electric fire.

    --
    Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
  16. Make Popcorn? by Xistenz99 · · Score: 2

    But can it fill a house with popcorn from that short burst?

  17. Can't melt steel beams by wasabioss · · Score: 1

    2 megawatts can't melt steel beams.

  18. I have a dream... by Zontar+The+Mindless · · Score: 1

    ...of a Slashdot where the editors actually edit submissions and turn them into something approaching standard English.

    When actual fucking EDITING commences, I'll consider that worth coming up with the bucks to fly out to Oregon and meet you guys at *Con. Thanks for the invite, though.

    --
    Il n'y a pas de Planet B.
  19. Re:Fukushima by Calydor · · Score: 1

    Because a whole country can only focus on one thing at a time!

    --
    -=This sig has nothing to do with my comment. Move along now=-
  20. Re:God damn it... by gsslay · · Score: 1

    Lol, this is a snafu, isn't it? We do have nimbies like yourself to put a stop to this kind of thing, but perhaps a quango should be set up to enforce it? People who insist in turning acronyms into words should be tasered and their zip code published online, so we can be sure they're on everyone's radar.

    I shall get a faq written up on this dangerous problem.

  21. Re:Fukushima by halivar · · Score: 1

    I bet you're a riot at parties.

  22. Proper Context by Fire_Wraith · · Score: 1

    Meanwhile, there's this other bit of news that's gone mostly unnoticed outside Japan: http://www.japantimes.co.jp/ne... Surely this must be coincidence, right? I think not! https://en.wikipedia.org/wiki/...

  23. Re:Enough to burn the Godzilla ? by jellomizer · · Score: 1

    Probably if it keeps up for more than a second. At least it will burn a small hole in it.

    --
    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
  24. Misleading power example by zelda64 · · Score: 1

    It compares the power needed to fire the laser for one picosecond to the power needed to run a microwave for 2 seconds. 2 seconds is 2 trillion picoseconds. So this laser draws enough power to run 2 trillion microwaves. Changes the entire context.

  25. Muhahaha! by DarthVain · · Score: 1

    Story only valid if scientist laughed maniacally before/during/after firing the worlds largest laser...

  26. Re:coming soon to a Death Star near you by Applehu+Akbar · · Score: 1

    You're going to blow up a planet of dyslexics?

  27. Re: God damn it... by bws111 · · Score: 1

    LASER is what is happening. laser is the name of the device.

  28. Comparison to NIF by Hydrated+Wombat · · Score: 1

    As many have pointed out 2 kJ 500 TW (goal power output of NIF) https://en.wikipedia.org/wiki/...

    1. Re:Comparison to NIF by Hydrated+Wombat · · Score: 1

      I welcome advice about how to include less than and greater than signs in a post.

    2. Re:Comparison to NIF by Hydrated+Wombat · · Score: 1

      This was supposed to be 2 kJ are much less than 2 MJ and 2 PW are larger than 500 TW

  29. worth of scientific proof reading ? ;) by AdrianFlorinLazar · · Score: 1

    excerpt from article. "Two quadrillion wattsit self is a massive amount of output. The burst only lasted about one picosecond (1/1,000,000,000,000 of a second), so while the energy output was incredibly large, the actual amount of power (energy divided by time) the LFEX used wasn’t all that big. When it was all said and done, the laser only produced enough power to run a microwave for about two seconds." they are wrong on this one. It's actually invers to how they explain. it's High Power - like in "Japanese Scientists Fire The Most Powerful Laser On The Planet" - and Low Energy. It must be Low Energy, because in other way, would be a tremendous quantity of energy E = P * t

  30. such small laser... by vettemph · · Score: 1

    Americans have mastodonic laser.

    --
    The government which is strong enough to protect you from everything is strong enough to take everything from you.
  31. Re:Fukushima by Calydor · · Score: 1

    Maybe these scientists are trying to make a laser powerful enough to shoot the radiation dead?

    --
    -=This sig has nothing to do with my comment. Move along now=-
  32. Out of work laser, will work for juice by rlh100 · · Score: 1

    What does an out of work laser do?
    Light up the night sky?
    Send a message to Alpha Centauri?
    Flash incinerate your pop corn?

  33. But Barack said it wasn't possible... by iq145 · · Score: 1

    Yet the japanese are building the Death Star http://www.newser.com/story/16...