Florida Researchers Create Shortest Light Pulse Ever Recorded

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Florida Researchers Create Shortest Light Pulse Ever Recorded

Posted by timothy on Thursday September 6, 2012 @09:50AM from the don't-blink-or-you'll-miss-it dept.

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."

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The width of a virus by hawguy · 2012-09-06 10:01 · 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 · 2012-09-06 10:40 · 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 · 2012-09-06 10:57 · 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 gnapster · 2012-09-06 16:27 · Score: 4, Funny
  
  Oh, give him a break. He only fucked it up a tiny bit.
4. Re:The width of a virus by deimtee · 2012-09-06 18:18 · 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...
5. Re:The width of a virus by Guignol · 2012-09-06 23:58 · Score: 2
  
  it's 13 even, since it was supposed to be 10 times that much ;)
Re:Video?!? by CanHasDIY · 2012-09-06 10:07 · Score: 4, Funny

Can't we get a video?
There was, but it was only 68 attoseconds long, so you must have missed it.

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Re:Short time, but ... by Zocalo · 2012-09-06 10:08 · Score: 4, Funny

tl;dr

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How do they measure this? by PhrostyMcByte · 2012-09-06 10:12 · 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 Anonymous Coward · 2012-09-06 10:35 · 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.
2. Re:How do they measure this? by The+Master+Control+P · 2012-09-06 10:51 · 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.
3. Re:How do they measure this? by Cyrano+de+Maniac · 2012-09-06 11:37 · 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
4. Re:How do they measure this? by Crypto+Gnome · 2012-09-06 11:42 · 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.
5. Re:How do they measure this? by Neil+Boekend · 2012-09-06 18:28 · 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.
1/1,000,000,000,000,000,000. What does that mean? by tim_darklighter · 2012-09-06 10:18 · 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.
Re:1/1,000,000,000,000,000,000. What does that mea by hawguy · 2012-09-06 10:38 · 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
Re:Video?!? by Roachie · 2012-09-06 10:56 · Score: 3, Funny

...buffering...

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Atto-boy!!! by trout007 · 2012-09-06 11:00 · Score: 2

Great job

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Re:How do you even measure this? by Mr.CRC · 2012-09-06 11:38 · Score: 4, Informative

http://en.wikipedia.org/wiki/Frequency-resolved_optical_gating
Re:Is there profit in it? by jo_ham · 2012-09-06 11:59 · 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.
Only 2 wavelengths of extreme UV by kipling · 2012-09-06 12:01 · 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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Re:color by Anonymous Coward · 2012-09-06 13:02 · Score: 2, Informative

If you know at what energy levels the photons are released, you know the wavelength.
Re:1/1,000,000,000,000,000,000. What does that mea by tim_darklighter · 2012-09-06 14:40 · 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.)
Re:Video?!? by CanHasDIY · 2012-09-07 02:13 · Score: 3, Funny

...buffering...
Buffering a 68 attosecond video?

Lemme guess - Comcast?

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An enigma, wrapped in a riddle, shrouded in bacon and cheese