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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
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.
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.
As far as my knowledge goes, yes the pump laser has to be X-ray. The energy of the emitted photons from the laser are always lower than the excitation energy of the lasing medium. So you need the high photon energy of x-rays to excite the medium to lase photons of lower (but still x-ray) energy.
Every experiment which ends in a big bang is a good experiment.
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
The LCLS isn't really a laser. It's a coherent synchrotron radiation source. But yes, intense x-rays are required to knock electrons out of the inner shells of the neon atoms.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Grazing incidence mirrors work well - we use them to steer the main X-ray beam. The mirror system we have works up to 24 KeV X-rays but with shallower angles you could go higher.
You can also use crystals to reflect X-rays over large angles - even 180 degrees using Bragg diffraction. The limit here is that the X-ray beam needs to be almost exactly a single wavelength.
--- Joe Frisch