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Scientists Create World's First Atomic X-Ray Laser
New submitter newmission33 writes "Government researchers have created the fastest, purest X-ray laser pulses ever achieved, and have fulfilled a 1967 prediction that an atomic scale X-ray laser could be made in the same manner as visible-light lasers, according to a statement released Wednesday. Researchers at the SLAC National Accelerator Laboratory used the Linac Coherent Light Source to aim a powerful X-ray source beam, a billion times brighter than any previous source, at a capsule of neon gas and triggered an 'avalanche' of X-ray emissions to become the world's first 'atomic X-ray laser.'"
Throw in a "jet" and "rocket" and I think we'll be all set.
What doesn't kill you only delays the inevitable
I don't mean if this is useful or not, the article clearly states how it is.
I mean, the pump laser, the one that excites the lasing medium (in this case neon gas). Does it have to be x-ray?
Would a coherent beam of some other, more easily produced frequency, or even a highly charged cathode beam, be sufficient to induce the xray emission cascade as well?
That will be difficult since your average bacterium lacks an anus - wait, what?
Nonsense.
This is a fantastic advancement. Remember those photographs of alkanes that showed the P orbital zones slashdot ran a story on sometime last year
Remember how fuzzy they were?
This badboy would make thoe pictures much, much clearer.
Disect the terms.
Atomic = the lasing medium is made of single, free atoms of the same element.
Xray = emits photons in the xray portion of the spectrum.
Laser = light is amplified by the stimulated emission of radiation. A source light source causes electrons in the laser's gain medium to fall out of their normal orbitals. When the fall back in, they emit a photon of a very specific wavelength. These photons bump more electrons out, more photons get produced, and the beam amplifies.
So, an atomic xray laser is a laser using atomic monomers as the gain medium, that produces coherent xray radiation.
Now then. Xray radiation is a powerful ionising radiation. This is not a toy. It does very bad things to living tissue, and can destroy chemical bonds purely from the beam's energy. It is a penetrating radiation, and is therefor dangerous even through walls. Keep out of reach of children and slashdot posters.
http://news.bbc.co.uk/2/hi/8225491.stm
These were taken with an AFM, (atomic force microscope. Essentially a single atom stuck to the end of a nanoscopic cantelever) but this xray laser light source would theoretically permit direct image capture, at very high speeds.
Xray wavelengths are very tiny. The only light with a smaller wavelength is gamma ray emissions.
Xrays are frequently used to study crystal structues, but the very precise nature and rapid activation speed of this source makes it useful for a whole lot more.
I wouldn't call this laser "the same manner as visible-light lasers" really, it lacks one of the fundamental features of a normal laser - self amplification via feedback from mirrors.
It sounds like this could be the _basis_ for a laser, as a pump source causes superluminescence, but without feedback it won't be particularly directional.
Perhaps if it can be triggered to start the avalanche at one end a directional burst could be achieved though, kind of like a nitrogen laser.
HIgher energy X-rays are penetrating, but these are of fairly low energy. The Nature abstract (http://www.nature.com/nature/journal/v481/n7382/full/nature10721.html) gives a bit more info. The X-ray energy is 849 eV. X-rays at this energy which are actually attenuated pretty well by air, and certainly by walls.
Remember how fuzzy they were?
This badboy would make thoe pictures much, much clearer.
Actually, those pictures are fuzzy partly because the orbitals themselves are fuzzy. You probably can't get much more detail than that; the detail doesn't exist.
At any rate, X-rays interacting with a single molecule like this one would likely knock electrons right off of it, thereby disrupting the very thing you're trying to image. Crystal X-ray diffraction imaging doesn't have that problem because of the countless copies of molecules available.
You probably can't get much more detail than that; the detail doesn't exist.
You just have to Zoom, then Enhance.
Nobodies Prefect
Tidbits for Techs Technology Blog
We treat the X-ray safety in a way similar to the high energy beam safety at the lab. Shielding, interlocked doors, monitoring, etc. For the soft X-rays in this experiment there is very little risk, they don't go far through air, but for hard X-ray operation we need to use more protection.
-- -Joe Frisch
The main X-ray laser is about a mile long. We are working on breeding bigger sharks......
That's how LHC works, they just use particles other than gamma rays. 3.5 TeV corresponds to wavelength of 2e-19 m.
Hmmm. Meant to publish that anonymously. Whoopsie. Hope I never run for office.
Hoist Number One and Number Six.