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Shark Science

Scientists Create World's First Atomic X-Ray Laser 145

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.'"
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Scientists Create World's First Atomic X-Ray Laser

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  • by SoupGuru ( 723634 ) on Thursday January 26, 2012 @09:04PM (#38835393)
    Throw in a "jet" and "rocket" and I think we'll be all set.
  • by wierd_w ( 1375923 ) on Thursday January 26, 2012 @09:10PM (#38835437)

    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?

    • by interval1066 ( 668936 ) on Thursday January 26, 2012 @10:12PM (#38835773) Homepage Journal
      "A laser is coherent light? So it talks?"
    • by toQDuj ( 806112 ) on Thursday January 26, 2012 @10:16PM (#38835799) Homepage Journal

      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.

    • by John Hasler ( 414242 ) on Thursday January 26, 2012 @11:12PM (#38836077) Homepage

      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.

      • What if you strongly ionized the neon prior to pump excitation?

        If you shred off the outer valences, and simultaneously expose the gain medium to a very strong positive static potential, the neon ions would be much easier to excite.

        Part of the energy in the emission would come from the already altered groundstate of the gain medium, rather than having to come from the pump source.

        Eg, you use a very hard UV laser, (much easier to make) and hold the neon in an electrically agitated state.

        It might not be as "cl

        • by EdIII ( 1114411 )

          It might not be as "clean" in terms of being a pure xray laser..(electrons bumped out of the containing vessel by the uv photons would be snatched up by the very electron hungry neon ions, releasing other species of photon.) But it would be easier to assemble.

          I have this image in my head.....

          Crazy Karlov's Weapon Emporium

          Karlov - "Why go to all the expense of purchase of commercial Death Ray? For just a fraction of price I build for you economical Death Ray from used weapons lab parts sold at auction by my cousin Mikhail. Ehhh, 70% powerful as those really expensive "military grade" models. Might leak some radiation and possibly explode, but nobody lives forever right!? Besides, one fried asshole smells like another fried asshole. I sweeten deal with some h

        • What if you strongly ionized the neon prior to pump excitation?

          If you shred off the outer valences, and simultaneously expose the gain medium to a very strong positive static potential, the neon ions would be much easier to excite.

          ...then reverse the polarity of the deflector dish. Right? I like to think im an intelligent person, but some of you people make me feel like im still in pre-school.

          • Think of it this way (extremely simple example follows):

            If you want to get to the meat of a walnut, you first have to crack the walnut shell. This requires some effort on your part.

            If, instead, you didn't have to crack the shell but had a bowl of walnut meat sitting in front of you, it requires much less effort to eat it.

            Same thing (I hope) with what the OP said. Instead of having to strip the "outer shell" of the ions at the same time you try to excite them, stripping them first THEN exciting them becomes

          • by mcgrew ( 92797 ) *

            I like to think im an intelligent person, but some of you people make me feel like im still in pre-school.

            Same here, and that's how I like it. It's nice having conversations with people smarter than me (or at least more educated in fields I know little about) after dealing with normtards all day. A day I learn something is a good day, and I often do at slashdot.

      • "The LCLS isn't really a laser. It's a coherent synchrotron radiation source. "

        Oh well fsck that clears it up! :) LOL

    • For this type of atomic X-ray laser I think the pump needs to have a higher photon energy that the lasing output. It is very much like a conventional laser except that the transitions occur at higher energies. If this is the experiment I am thinking of it was done a while ago but probably just published. Its a very nice demonstration.

      Joe Frisch
      SLAC / LCLS

    • Not having read the research, I feel unencumbered by facts so I'll speculate. Irresponsible, I know, but such fun!

      Maybe it wouldn't take an X-ray excitation source if a lower energy source were bright enough. I presume there's some energy transition in the Ne electronic structure that SLAC's X-ray flashlight pumps to make the coherent X-ray emission they seek. Maybe the X-ray pump is high enough energy that each X-ray photon has enough energy to pump the Ne transition. This sounds like linear absorption t

    • by EdZ ( 755139 )
      It would have to be a higher energy (shorter wavelength) pumping input, e.g. a gamma ray pulse [].
    • by LoRdTAW ( 99712 )

      At first I thought they were talking about a nuclear pumped laser [].

      Its interesting to see a new bright and fast x-ray source for study. The short pulses of the atomic x-ray are useful for micro/nanoscopic imaging as you emit a pure, ultra bright yet short pulse of x-rays that penetrate the subject without frying it. Think of it as a camera flash that allows you to see through things without cooking/vaporizing them and is fast enough to capture things happening in a quadrillionth of a second. I only wish a li

  • They weren't x-rays they were z-rays but z is just as good as x in fact better.

  • "The Crossbow Project. There's No Defense Like a Good Offense."

    • What else did you think a super phase conjugate tracking system is for?
    • Yes, but would you be prepared if gravity reversed itself?
    • I'm just pondering the immortal Socrates who said, "I drank what?"
    • "The Crossbow Project. There's No Defense Like a Good Offense."

      I find this offensive. Furthermore, you neglect to acknowledge several defensive strategies than are like a "Good Offense"... Such as derogatory remarks followed by the phrase "No Offense".

  • of reading Larry Niven and Jerry Pournelle, and wishing I could find an abandoned museum with a freakin' x-ray laser in it.
    • of reading Larry Niven and Jerry Pournelle, and wishing I could find an abandoned museum with a freakin' x-ray laser in it.

      Yes, I too suffer from not being able to find certain artifacts within my own memories...
      Now where did I put that Epsilon-Ray laser?

  • by Anonymous Coward

    But will it blend?

  • by Laser Dan ( 707106 ) on Thursday January 26, 2012 @09:50PM (#38835681)

    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 [].

    • by wierd_w ( 1375923 ) on Thursday January 26, 2012 @09:58PM (#38835713)

      I can't think of any materials with which to create an xray mirror... not of sufficient quality anyway. Without some of those, and an xray beam splitter, you couldn't possibly self amplify...

      If this were built on a very tiny scale, so that the neon atoms were all in a row (trap them inside a nanotube maybe?) Perahps a nanoscale version could be made directional? (Or at least have a directional bias)

      • by Anonymous Coward

        I could be way off base, but ISTR hearing that X-rays reflect well off some metals (or metal-on-glass) at low (grazing) angles of incidence, which would permit a multiple-mirror resonance circuit. Of course, it'd be hell to align, and the multiple reflections might cause too much loss...

        • by joe_frisch ( 1366229 ) on Thursday January 26, 2012 @11:16PM (#38836105)

          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

    • This would be neither as directional nor as coherent as a conventional laser because of the lack of those mirrors. Those are properties that follow from having a high quality resonator. It may be (IMO is) impossible to duplicate those properties with x-rays.

    • A resonator is not an essential feature of a laser (Light Amplification by Stimulated emission of Radiation).

      • Yes, a resonator is an essential feator of a laser. The acronym is a bit of a misnomer. A light amplifier itself does not make a laser. A Laser must make coherent light, and that happens through 1) a gain medium and 2) an oscillator.
        • by Ruie ( 30480 )
          LASER - light amplification by stimulated emissing of radiation. So it could just be an amplifier. However, even if you want directionality the resonator is still not necessary - you just need to assure that the mode of your choice has higher gain than other modes.

          For example, make your lasing medium into a long thin rod - it will emit along the rod axis (in both directions).

        • by c0lo ( 1497653 )

          Yes, a resonator is an essential feator of a laser.

          No, it's not as this example [] demonstrates.

          Even better, a quote from here []:

          Because of high gain in the lasing medium, short upper-state lifetimes (1–100 ps), and problems associated with construction of X-ray mirrors, X-ray lasers usually operate without any resonator.

  • Where are the atomic-level sharks with atomic-level lasers attached to their heads?
  • This will probably be handheld.
  • Where I can get a few fricken sharks?
    • If you want fricken sharks you must frack them yourself.
      No one's foolish enough to believe they're toothy mermaids anymore.
  • Just saying...
  • the first use I thought for such a device was to make home-size non-Uranium nuclear reactors (Thorium, Hafnium) a practical reality.
    • by necro81 ( 917438 )
      Unfortunately, I don't think this will be useful for that at all, for two important reasons:

      1) X-rays, although pretty potent in the grand scheme of things, are too wimpy to influence, and certainly cannot initiate, nuclear reactions. X-rays tend to interact with the electron cloud around atoms, and so don't penetrate down as far as the nucleus. Bombarding a slug of some fissile material with X-rays will only yield a lot of scattered X-rays; the nuclear decay will be more or less unaffected.

      2) The f
  • My guess is the x-rays travel at 299,792,458 m/s - just like every other photon.

    Perhaps the poster's meaning is "pulse with the shortest duration"

    • Don't forget the avalanche period.

      A laser is a stimulated light source. It emits under stimulation. Part of that stimulation is self generated.

      Like a transistor, it continues to operate for a short time when the source of the stimulation gets shut off. Likewise, when the beam is turned on, it takes a tiny amount of time for the photon avalanche to occur. (Speed of photon propogation is not the same as C in vaccuum.)

      Thus, the speed of the laser is how fast it is on/offable.

  • []

    (when head-mounted on shark, you don't get your shark back)
    • by JTsyo ( 1338447 )
      seems it would be easy to defeat by launching waves instead of just one large wave.
      • Back in the days of a mostly ground based ICBM force, delaying launch means losing the weapons to inbound ones.
  • With fabs already using DeepUV lasers and phase-shifting masks, the ability to do x-ray pulses would seem to me (I am not a phsyicist) to make it possibly to use for wafer lithography to produce much smaller chip geometries than we have today. A pulse laser would make it much easier to do that without damaging the chip (since x-rays are very freaking energetic indeed). So Moore's Law might get a new lease on life, assuming that this technology is capable of being commercialized.

    • by treeves ( 963993 )

      IIRC ASML already claims to have an EUV scanner capable of 69 wafers per hour throughput, using discharge-produced (tin?) plasma.
        I really doubt any company is going to want to spend a ton more cash and several years to get ANOTHER method of EUV imaging working after all the time and $$ it has taken to get where we are today.

      • by necro81 ( 917438 )
        The latest I heard [] indicates that EUV is still having a tough time getting going. The light source isn't bright enough, so throughput is too low to be commercially viable. ASML may claim to have a source capable of exposing 69 wafers per hour, but it's not like those machines are rolling off the assembly line right now.

        Some other people out there are investigating using free-electron lasers to produce EUV, either directly as the output of the FEL, or by using the FEL to stimulate EUV emission in some o
        • by treeves ( 963993 )

          Yeah, the fabs really want 100+ wafers/hr, and I'm not sure about the debris problems with DPP EUV sources being solved, but brightness seems to be getting there, and to totally switch technologies seems like a big risk. I know, sunk cost fallacy and all that...

  • Why should black holes have all the fun?

  • MIT prof Peter Hagelstein made one in the 1980s while working for energy labs. This fell into the class of "3rd generation nuclear weapons" which included very customized radiation outputs. And this excited Teller and Reagan into the "Star Wars" defense shield program. I dont think that program is dead yet, but highly morphed.
  • To cookoff munitions inside a tank?