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Florida Researchers Create Shortest Light Pulse Ever Recorded

timothy posted about 2 years ago | from the don't-blink-or-you'll-miss-it dept.

Shark 76

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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shortest pulse of light? (-1)

Anonymous Coward | about 2 years ago | (#41253989)

I thought that was Lindsay Lohan ...
(captcha: lotion)

Video?!? (0)

Kergan (780543) | about 2 years ago | (#41254029)

Re:Video?!? (4, Funny)

CanHasDIY (1672858) | about 2 years ago | (#41254091)

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

Re:Video?!? (3, Funny)

Roachie (2180772) | about 2 years ago | (#41254587)

...buffering...

Re:Video?!? (3, Funny)

CanHasDIY (1672858) | about 2 years ago | (#41259755)

...buffering...

Buffering a 68 attosecond video?

Lemme guess - Comcast?

Re:Video?!? (0)

Anonymous Coward | about 2 years ago | (#41255557)

No, it was subject to Algorthmic takedown, see the article "The Algorithmic Copyright Cops: Streaming Video's Robotic Overlords" above.

Re:Video?!? (1)

ObiWanKenblowme (718510) | about 2 years ago | (#41260579)

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

Re:Video?!? (1)

Razgorov Prikazka (1699498) | about 2 years ago | (#41254193)

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

Re:Video?!? (0)

Anonymous Coward | about 2 years ago | (#41258285)

Interesting video

Re:Video?!? (1)

Guignol (159087) | about 2 years ago | (#41258573)

Awesome, thank you

I guarantee this involves... (-1, Flamebait)

Anonymous Coward | about 2 years ago | (#41254031)

...some attempt to measure Asian weiners.

The width of a virus (5, Informative)

hawguy (1600213) | about 2 years ago | (#41254037)

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

Re:The width of a virus (-1)

Anonymous Coward | about 2 years ago | (#41254111)

And it's 10 times the length of your micropeen.

Re:The width of a virus (5, Funny)

Fned (43219) | about 2 years ago | (#41254599)

Attopeen, you idiot.

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

Re:The width of a virus (4, Funny)

gnapster (1401889) | about 2 years ago | (#41256789)

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

Re:The width of a virus (2)

deimtee (762122) | about 2 years ago | (#41257309)

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

Re:The width of a virus (2)

Guignol (159087) | about 2 years ago | (#41258617)

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

Re:The width of a virus (1)

Hillgiant (916436) | about 2 years ago | (#41259625)

Yes. But they are very small orders of magnitude.

Re:The width of a virus (3, Interesting)

Calydor (739835) | about 2 years ago | (#41254421)

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.

Only 2 wavelengths of extreme UV (2)

kipling (24579) | about 2 years ago | (#41255219)

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.

Re:The width of a virus (1)

snikulin (889460) | about 2 years ago | (#41256395)

7.90791129 × 10-7 inches!

Sub-Atomic Strobe Light Party! (1)

AlienSexist (686923) | about 2 years ago | (#41254043)

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

Re:Sub-Atomic Strobe Light Party! (1)

dimeglio (456244) | about 2 years ago | (#41258293)

Hollywood, are you listening?

Short time, but ... (1)

ackthpt (218170) | about 2 years ago | (#41254047)

longer than my attention span

Re:Short time, but ... (4, Funny)

Zocalo (252965) | about 2 years ago | (#41254109)

tl;dr

Re:Short time, but ... (0)

Kjella (173770) | about 2 years ago | (#41254605)

It's slashdot, mark parent redundant ;)

Calculating the length of the beam (0)

Anonymous Coward | about 2 years ago | (#41254055)

You can work out the length of the beam this would produce using Wolfram Alpha. Enter the query:

      speed of light in a vacuum * 67 attoseconds

and you get the result: 20 nanometres. Interestingly, that's about the same size as current chip fabrication technology.

Re:Calculating the length of the beam (-1, Flamebait)

Anonymous Coward | about 2 years ago | (#41255653)

Wolfram Alpha?? You must know that that c is 3e8 m/s already. Surely multiplying by 67e-18 s is not that hard without google.

You can even do it in your head if you can't find a calculator. 67 attoseconds is 67e-18. Add the exponents of that and 3e8, -18 and 8 and you get an exponent of -10. Multiply the mantissas 3 and 67; well 67 is about two thirds of a hundred, times the 3 of 3e8 so it's 200. Include the exponent and it's 200e-10, or 20e-9, i.e 20 nanometres. Done

How do you even measure this? (1)

Anonymous Coward | about 2 years ago | (#41254077)

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

Re:How do you even measure this? (4, Informative)

Mr.CRC (2330444) | about 2 years ago | (#41255005)

Re:How do you even measure this? (0)

Anonymous Coward | about 2 years ago | (#41255597)

Interesting...

I can beat that! (0)

QilessQi (2044624) | about 2 years ago | (#41254125)

I can create a laser pulse lasting ZERO attoseconds. There, just did it. There, just did it again. Top *that*, UCF!

Re:I can beat that! (1)

ThatsMyNick (2004126) | about 2 years ago | (#41254231)

Are you sure that was a laser pulse?

How do they measure this? (3, Interesting)

PhrostyMcByte (589271) | about 2 years ago | (#41254159)

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?

Re:How do they measure this? (0)

Anonymous Coward | about 2 years ago | (#41254259)

12 attoseconds is the world record for shortest controllable time
http://phys.org/news192909576.html

Re:How do they measure this? (1)

BMOC (2478408) | about 2 years ago | (#41254323)

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.

Re:How do they measure this? (0)

Anonymous Coward | about 2 years ago | (#41256171)

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.

Based on some of the timing debacles this year, I'd say they're struggling enough as-is...

Re:How do they measure this? (0)

harrkev (623093) | about 2 years ago | (#41254271)

Also, how powerful was the pulse?

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. Of course, one single photon is not really good for much, You really need a lot of photons to do anything useful.

Re:How do they measure this? (0)

Anonymous Coward | about 2 years ago | (#41254319)

It is EASY to create the world's shortest laser pulse: emit a single photon.

No you cannot.

Re:How do they measure this? (1)

stevelinton (4044) | about 2 years ago | (#41254455)

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.

Re:How do they measure this? (2)

Cyrano de Maniac (60961) | about 2 years ago | (#41254989)

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.

Re:How do they measure this? (1)

JoeRobe (207552) | about 2 years ago | (#41256415)

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).

Re:How do they measure this? (4, Interesting)

The Master Control P (655590) | about 2 years ago | (#41254537)

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.

Re:How do they measure this? (2)

Neil Boekend (1854906) | about 2 years ago | (#41257357)

Unless you're the Doctor.

Re:How do they measure this? (5, Informative)

Anonymous Coward | about 2 years ago | (#41254349)

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

The technique is called Frequency-Resolved Optical Gating [wikipedia.org] (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.

Re:How do they measure this? (1)

WSOGMM (1460481) | about 2 years ago | (#41254389)

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 [ksu.edu]

Detection: Phase Retrieval by Omega Oscillation Filtering

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

Re:How do they measure this? (1)

retchdog (1319261) | about 2 years ago | (#41254511)

``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).''

Re:How do they measure this? (2)

Crypto Gnome (651401) | about 2 years ago | (#41255043)

``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.

Re:How do they measure this? (0)

Anonymous Coward | about 2 years ago | (#41260529)

``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.

For that.., youre gonna need a MON-TAGE!!!

insert scientist staring at clipboard, scientist frowning at beakers on a bench, scientist lifting weights in a sweatsuit, and finally scientist observing shortest light pulse ever, then high-fiving and chest bumping

Re:How do they measure this? (0)

Anonymous Coward | about 2 years ago | (#41254547)

It is not possible to measure these kinds of pulses directly as there's nothing to compare it to. Instead it must be calculated by transforms or other interference effects.

Re:How do they measure this? (1)

communiss (1918882) | about 2 years ago | (#41254693)

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.

Not fast enough (0)

FranTaylor (164577) | about 2 years ago | (#41254177)

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

Re:Not fast enough (1)

drkim (1559875) | about 2 years ago | (#41257063)

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.

1/1,000,000,000,000,000,000. What does that mean? (5, Interesting)

tim_darklighter (822987) | about 2 years ago | (#41254191)

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 (4, Insightful)

hawguy (1600213) | about 2 years ago | (#41254397)

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:1/1,000,000,000,000,000,000. What does that mea (1)

oobayly (1056050) | about 2 years ago | (#41254477)

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.

Re:1/1,000,000,000,000,000,000. What does that mea (2)

tim_darklighter (822987) | about 2 years ago | (#41256335)

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:1/1,000,000,000,000,000,000. What does that mea (1)

fnj (64210) | about 2 years ago | (#41256809)

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.

Re:1/1,000,000,000,000,000,000. What does that mea (1)

Neil Boekend (1854906) | about 2 years ago | (#41257393)

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.

Re:1/1,000,000,000,000,000,000. What does that mea (0)

Anonymous Coward | about 2 years ago | (#41262445)

I think for most people who don't get 1 x 10^-18, 1/1,000,000,000,000,000,000 looks like a really _big_ number because they are too clueless to notice the 1/ bit, or really internalize what it means.

Re:1/1,000,000,000,000,000,000. What does that mea (0)

Anonymous Coward | about 2 years ago | (#41255957)

As a photochemist, I know that a femtosecond [...] is the on order of many "fast" chemical reactions

In what sense is that? I would imagine that ultimately chemical reactions are instantaneous, that is, quantum state changes.

Similarly, I don't understand the summary's talk about watching electrons move within atoms. AFAIK, electrons don't move on their orbitals but are stationary until they participate in an interaction.

Re:1/1,000,000,000,000,000,000. What does that mea (1)

jeffmeden (135043) | about 2 years ago | (#41260587)

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?

fiber network benefits? (0)

Anonymous Coward | about 2 years ago | (#41254233)

Would stuff like this benefit fiber networking by any chance? A lot more pulses in a much shorter time frame would boost bit transfers would it not?

Re:fiber network benefits? (0)

Anonymous Coward | about 2 years ago | (#41255021)

The issue with using waves for communications is that you have to find a balance between bit rate and range. For a single bit to be transmitted, a certain number of periods need to be transmitted. I don't know the theoretical limit but for argument's sake let's set it to one. To transmit information quicker, you need to shorten the duration of the period, i.e. increase the frequency. But when you increase the frequency, the radiation is can't travel around corners that easily (diffraction). Additionally, higher frequency means higher energy consumption. Then there's issue of finding the optimal material that can transmit light of that frequency through hundreds of kilometers without much loss. Converting pulses to electrical signals is another issue. Processing electrical pulses at similar rate is yet another issue.

To answer your question, yes, it increases theoretical limit at which we can transmit data. But there's lot more engineering and research needed to take advantage of this new achievement.

Re:fiber network benefits? (1)

joe_frisch (1366229) | about 2 years ago | (#41255073)

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.

Photography (0)

Anonymous Coward | about 2 years ago | (#41254625)

Now maybe we can get a picture of the fastest thing in the world, that drop of water that shoots up your butt when you take a good dump.

Atto-boy!!! (2)

trout007 (975317) | about 2 years ago | (#41254633)

Great job

If it gets to the point... (0)

Anonymous Coward | about 2 years ago | (#41254931)

where we can see God rolling the dice, he might be very impressed and lets us back into the Garden.

Re:If it gets to the point... (1)

jellomizer (103300) | about 2 years ago | (#41258659)

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.

Is there profit in it? (1)

bobs666 (146801) | about 2 years ago | (#41254933)

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.

Re:Is there profit in it? (3, Insightful)

jo_ham (604554) | about 2 years ago | (#41255203)

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.

color (1)

dmitrygr (736758) | about 2 years ago | (#41255261)

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?

Re:color (2, Informative)

Anonymous Coward | about 2 years ago | (#41255759)

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

Re:color (0)

Anonymous Coward | about 2 years ago | (#41257397)

First of all you would not be able to create a pulse that short with discrete energy levels.
As you noticed you would have only one frequency and hence there would be no way for creating short pulses.
Actually you have to use laser materials with broad bads.

You can see this as a manifestation of the uncertanty priciple (even though it is just a fourier transformation of the puleses spectrum in this case).
If you have a very short time (laser pulse) you do not know the exact energy.
Translating this means that for ultra short Pulses you need MANY different photons with different energies - so you dont know the wavelength.

Just for completeness:
By the way, every photon itselve is in a superposition of all the wavelength of the puses' spectrum.....

Re:color (0)

Anonymous Coward | about 2 years ago | (#41256459)

UV can refer all the way down to 10 nm.

what about quantum? (1)

ethorad (840881) | about 2 years ago | (#41258901)

"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?

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