Fastest-Ever Flashgun Captures Image of Light Wave

loconet writes to tell us that a team of researchers have created the shortest-ever flash of light. Weighing in at just 80 attoseconds, this flash has already been used to capture an image of a laser pulse and could possibly be used in the future to capture the electron movement around large atoms.

Comments

Who woulda thought?

[rumblin'rabbit]

My God, James Clerk Maxwell was right after all!

Re:Who woulda thought?

[vivin]

Light is a wave and a particle and therefore, a "wavicle".

Re:Who woulda thought?

[CaptainPatent]

My God, James Clerk Maxwell You crazy Slashdotters and your false idols! :-)

Re:Who woulda thought?

[PunkOfLinux]

Ergo, test particles are "testicles"?

Re:Who woulda thought?

[turgid]

Ergo, test particles are "testicles"?

No, he was a famous ancient Greek philosopher.

Re:Who woulda thought?

[bugnuts]

Would that be the famous double-slit experiment?

Re:Duckhunt

[andrewd18]

Newsline Saturday: Hundreds of mallard ducks found dead outside residential area; experts believe death caused by epileptic seizures.

Re:Taking a picture of a laser beam and using flas

[Jeremiah Cornelius]

Because it's there. Well.. no... I mean it's "there", now. Oh. I mean by now it's all the way over there...

Dang! You know what I mean!

Yep, it's hoax.

[Anonymous Coward]

It is a hoax. see the picture of the light pulse? Well, for one, it's only showing a wave and we all know from physics that light is both a wave and and particle. So where's the particle? Hmmm?

Secondly, the wave is, well, wavy. And we know, again from physics, that light only travels in a straight line.

Those damn scientists always trying to fool us! And engineers too!

Re:Sounds impossible

[bugnuts]

from TFA, I believe it's imaging a laser pulse shot through neon gas. It's the laser pulse that triggered the flash in the first place.

Bizarrely, the article states

As each flash is intense enough to completely ionise a neon atom and release an electron, the researchers could use those electrons like a flashgun, to illuminate some of the original 2.5 femtosecond trigger pulses of laser light. This is interesting, because the neon is releasing electrons, not photons.

I agree that snapping a photo of light sounds dubious, but it looks like an electron flash, so maybe it's just making something visible that wouldn't have been seen otherwise.

Re:Duckhunt

[PawNtheSandman]

What's the difference between you and a mallard with a cold?

One's a sick duck and... I can't remember how it ends, but your mother's a whore.

Um... What?

[barfy]

Ok, Internet Physicists out there, please help me.

Ok, first you have this coherent photon beam. This means that they are all traveling at the same direction. So how do you take a picture of THAT?

You are bombarding the photon beam with photons, are the photons opaque, reflective, or TRANSPARENT? How do the photons from the flash, BOUNCE BACK at the camera. When they bounce back, how do you get color?

Is it just me, or does this make any sense at all?

Re:Um... What?

[Btarlinian]

From the article it sounds like a pump-probe experiment. They excite the neon with a 2.5 femtosecond pulse and then image the excited state with a 80 attosecond pulse. (You obviously need the imaging pulse to be shorter than the excitation pulse.) I'm not sure how much detail you would be able to get from this though, as the wavelength and brightness of the light source would be a limiting factor.

Re:Um... What?

[againjj]

Ok, first you have this coherent photon beam. This means that they are all traveling at the same direction. So how do you take a picture of THAT?

In a different way that a standard photograph.

You are bombarding the photon beam with photons,

No, you aren't. That doesn't make sense.

What they do is have the laser pulse travel through something they call a "chirped mirror". This packs the photos from the laser pulse into a smaller space. This then travels through a neon cloud, which then creates a flash of light. This flash of light is the "shortest-ever flash of light".

To photograph this flash of light, they direct it into a second neon cloud, which ionizes atoms, releasing electrons. Those electrons are then recorded. Multiple flashes were required to produce enough electrons to build up the image shown in the article, so what you really have is an image of many flashes overlaid.

Re:Um... What?

[TigerNut]

Richard Feynman once pondered, if moisture molecules in the atmosphere scatter light, and presumably this is a random effect because the molecules are randomly distributed, why is it that buildings, etc. when they're viewed through mist, do they still have sharp edges? You'd think all the random scatter would blur the edges.

That thought train led him to do some fundamental work in particle scattering and path integrals, IIRC, and eventually to the Feynman diagrams that are now commonly used to describe some aspects of particle interactions.

So you're thinking some good deep thoughts there, but I can't give you a good answer other than "they just know". Basically the "proper" reflection is the only one that is coherent to the observer and the other reflected beams are all out of phase so they might as well not happen... and therefore they don't. Or something like that.

Re:Um... What?

[BlackLungPop]

Check out the book QED: The Strange Theory of Light and Matter, by Richard Feynman. The answer is basically that the photon doesn't bounce off of anything! It "interacts" with an electron, and another photon is emitted. Why is it emitted at the particular angle? That's what the book is all about. Way too much to explain here. But if you want to understand in layman's terms how reflection and refraction work, and why glass is transparent, get that book, it's wonderful.

Ummm..

[InlawBiker]

I hate to be a pedantic killjoy, but on that film the light flash lasted about 3 seconds. I could see it pretty well with my naked eye.

Try again, science!

Re:What about shutter speed?

[egomaniac]

Consider a 35mm film camera with a mechanical shutter... what degree of force and mechanism would be required to move that shutter to open AND close the height of 24mm in 80 attoseconds? IANAPhysicist, but I doubt human hands could hang on to it.

Apparently we're not realizing just how short 80 attoseconds is. You doubt human hands could hang on to it? Moving 24mm in 80 attoseconds is faster than the speed of light. Not only is it faster than the speed of light, it's a million times faster than the speed of light.

Light only travels 24 nanometers in 80 attoseconds.

Re:Duckhunt

[gardyloo]

At which point she laughs?

Re:Duckhunt

[dotancohen]

My girlfriend tells a joke about ducks. It goes:

"What's the difference between a grape and a duck?"
Answer: "Both are purple, except for the duck."

Yeah, it's stupid, but I laugh, and then she has sex with me.

Tell her I laughed. How far does she live from Nesher?

Re:What about shutter speed?

[kjots]

Your safe search is off, which triggers my URL filtering to block google. It's a great way to catch people who hang out on the seedier side of google images.

Or people who don't like to have their search results artificially curtailed by someone else's sense of unreasonable morality.