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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.'"
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.
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.
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.
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
That's how LHC works, they just use particles other than gamma rays. 3.5 TeV corresponds to wavelength of 2e-19 m.