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Researchers Chill Mirror to Near Absolute Zero 202

An anonymous reader writes "Physicists have managed to cool a dime-sized mirror to within one degree of absolute zero. This is the lowest laser-induced freeze yet achieved with a visible object. Laser cooling involves firing pulses of light at a specific frequency that exactly matches an atom's motions."
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Researchers Chill Mirror to Near Absolute Zero

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  • See, kids? (Score:3, Funny)

    by FlyByPC ( 841016 ) on Wednesday April 11, 2007 @11:59PM (#18698235) Homepage
    Science *is* cool. Sometimes literally!
  • Mirror (Score:5, Interesting)

    by biocute ( 936687 ) on Thursday April 12, 2007 @12:00AM (#18698253) Homepage
    What's the significance of chilling a dime-sized mirror, vs chilling a dime?
    • I imagine that (Score:5, Informative)

      by pavon ( 30274 ) on Thursday April 12, 2007 @12:11AM (#18698295)
      the surface has to be highly reflective for this to work. If it absorbed the photons, then it's temperature would increase, and if it was transparent the photons wouldn't interact with the material very much, and thus would not be able to cool it.
      • by weighn ( 578357 )
        IANAP, but I'd guess that a super-flat surface is needed so they can have a precise measurement of the distance between the laser and the object being zapped. That way they can time the laser freq with the atomic vibrations. There's just too many mountainous bumps on a dime.
        • The beauty of laser-cooling is that surface roughness (on a moderate scale; the face of a dime is pretty rough, but a "smooth" piece of metal probably wouldn't affect things too much) isn't a problem. Nor are small motions in the direction of the laser axis. In fact, it's the doppler effect of the motions to and fro in the laser beam axis that *helps* laser cooling work. It's nice to have atomic transitions near the laser's frequency, but it's not especially necessary. And I kind of doubt that phonons prese
    • Re:Mirror (Score:5, Funny)

      by glwtta ( 532858 ) on Thursday April 12, 2007 @12:17AM (#18698327) Homepage
      Makes you look cool?
    • Probably about $99,999.90. Im guessing that the mirror had to be specifically designed!
    • Well, when they get the mirror close enough to absolute zero, apparently it will "show its quantum behavior for the first time," which I assume means it will reflect THE FUTURE.
    • What's the significance of chilling a dime-sized mirror, vs chilling a dime?

      No idea, but the significance of chilling WITH a dime is that I'm high as hell on some stinky, stinky weed.

      JK, Mom.
  • This should answer the age old question, if a mirror at absolute zero breaks, do you have bad luck?
  • by Barkmullz ( 594479 ) on Thursday April 12, 2007 @12:26AM (#18698377)
    IANAP, so I figured this was some sort of breakthrough. As it turns out:

    1. Others have gotten much, much closer to 0 K using atoms and laser cooling.
    2. Others have gotten much, much closer to 0 K using solid objects and different cooling methods.
    3. Their method has the potential of getting closer to 0 K.

    So, even if it is not a breakthrough it is still impressive.
    • by btgreat ( 895041 ) on Thursday April 12, 2007 @01:42AM (#18698725)
      Actually, this really is a breakthrough. According to the article, laser supercooling has been used in the past by researchers, but never on anything more than a few atoms. These researchers successfully lasercooled a mirror the size of a dime (which would probably be about .01 to .1 moles, on the order of 10^21 or 10^22 atoms, more than just "a few" (probably meaning on the order of 10^6 or so, but IANAP, so don't quote me there)).
    • Re: (Score:3, Informative)

      by imsabbel ( 611519 )
      What _you_ seem to know as laser cooling is esentially using a modified penning trap with 6 circular polarized lasers. There is no way to use such an assembly on any _visible object_ (thats why that sentence was used in the blurb). It needs the volume of entrapment to be translucent.
  • by edwardpickman ( 965122 ) on Thursday April 12, 2007 @12:44AM (#18698465)
    My exwife could do that with just a glance. It may not have been one degree over Absolute Zero but it sure felt that way.
  • by The Great Pretender ( 975978 ) on Thursday April 12, 2007 @01:16AM (#18698599)
    You want to get to absolute zero, go see my first wife
  • Now we would all be a lot more impressed if they cooled a glass of Guinness down to the requisite 5 degrees Celsius.

    A functional laser operated beer cooler... now that would be a patent i wouldn't complain about.
    • by weighn ( 578357 )
      ...requisite 5 degrees Celsius...

      although the "serve at room temperature" thing is a bit of a myth for Irish/British beers, the best temp for pouring a Guinness [] is around 7-8 degrees. Sounds like I'm nit-picking, but there is a difference for us piss-heads^H^H^H connoisseurs.

  • by XchristX ( 839963 ) on Thursday April 12, 2007 @01:36AM (#18698689)
    The JILA group at UC Boulder does lots of work on laser cooling and trapping (the Weimann/Ketterle/Cornell group got the 2001 Nobel Prize for generating BEC by laser cooling). They have a neat java applet demonstrating the effect html []
    • Just a nitpick, but the UCs are in California (University of California) and U of Colorado is called CU. So it's CU-Boulder.
  • A couple of people made posts that got my brain ticking.. Someone mentioned that this confirms quantum theory in that adding light energy reduces the temperature, thereby reducing the energy of the system. In response, someone mentioned it was like noise cancellation. The problem I see with this analogy, and the idea of the experiment in general is that while I can see similarities, when we talk about noise cancellation, no energy is lost. It is still there, even though destructive interference cancels th
    • Re: (Score:3, Interesting)

      by smaddox ( 928261 )

      We start with high speed atoms and light, and end with low speed atoms and no light; isn't the energy being destroyed?
      You actually DO end up with light. More energetic light, to be more specific.

      It can almost be simplified to classical collision physics. The photon hits the atom and bounces off, slowing down the atom and in turn, the photon "speeds up" (gets red shifted).
  • "Laser cooling involves firing pulses of light..." I believe Victor Fries [] would be proud.
  • Using LASER cooling to bring a macroscopic object o 0.8K is pretty darn neat. But cooling big things in general to sub-Kelvin temperatures is not that unusual (the article only gives a nod to this idea). For example, in our bolometry experiment [], we cool 40 kg of TeO2 crystals down to just 10 milliKelvin using an ancient Oxford (brand) dilution refrigerator.
  • by Derling Whirvish ( 636322 ) on Thursday April 12, 2007 @02:14AM (#18698895) Journal
    When will we see this technique used to cool the CPUs in gaming machines?
  • If the mirror was cooled lower still it supposedly would exhibit quantum effects, TFA says. Would this mean the mirror could interfere with itself, like in the single photon double slit experiment? How could this create more sensitive mirrors for the LIGO?
  • Oblig. (Score:3, Funny)

    by SeaFox ( 739806 ) on Thursday April 12, 2007 @02:35AM (#18698977)
    "Mirror, Mirror on the Wall, who's the coolest one o-- AAAAAAAH! MY EYES!

  • by viking80 ( 697716 ) on Thursday April 12, 2007 @02:54AM (#18699089) Journal
    There must be some error in TFA. Looks like it was written by someone with little understanding. To cool a 1g item under 1K is trivial. You can buy coolers that can keep large volumes way down in the mK range. Commercial literature give numbers like 1mW cooling at 35mK.

    TFA says that the purpose of cooling was to "...cancel the natural forces entirely, so quantum forces apply exclusively."

    That is of course incorrect. Quantum mechanics *are* the natural forces(,excluding gravity?), and cooling is often used to bring matter to the ground state or similar, so quantum effects take on macroscopic and often more observable (and intriguing) properties.

    If there is a real breakthrough here, does anyone have the original scientific reference?
  • Laser Cooling (Score:3, Informative)

    by FreemanPatrickHenry ( 317847 ) on Thursday April 12, 2007 @03:05AM (#18699165)
    "Laser cooling involves firing pulses of light at a specific frequency that exactly matches an atom's motions."

    I may be wrong on this, as I'm just an undergrad physics major, but in my experience laser cooling involves detuning a laser slightly below some atomic transition frequency, and counterpropagating the same beam back. What happens is as a laser moves quickly in the direction of the beam, it observes the laser's frequency to be higher due to the Doppler shift, and suddenly this laser that was not resonating with the atoms comes into resonance, and the atom starts absorbing photons, which have momentum. This knocks the atom back such that it can't move quickly in the direction of the laser. Often this is done with six beams along three orthogonal axes so that you cool the atoms in all directions.
  • If ... (Score:2, Interesting)

    by can56 ( 698639 )
    Scientists can use lasers to cool atoms/crystals/mirrors to near absolute zero, does that mean: a) really god-damn-cold-fusion is possible, or b) by increasing the power of the lasers, hot-fusion may occur?. Sorry, but I'm waiting for someone (less drunk and more eloquent than I) to comment on the definition of temperature, the scales (K/F/C), and what this experiment could lead to.
  • their laser goes up to 11, which might have allowed them to get below 1 degree!
  • In the 21st century, the evolution of ice beer continued unabated...
  • My refrigerator repair man was explaining to me in a very pedantic way that a refrigerator doesn't make cold, but rather it moves heat out of the inside and pushes it to the outside. This is the conservation of energy.

    If a laser can counter the speed of atoms, thus creating an object at near absolute zero, couldn't this create a cold environment without creating equal heat outside the environment? Am I misunderstanding the experiment or are they creating cold without removing heat?

    The applications of this
  • I have always wanted the reverse of a Microwave, something that can rapidly cool food/drink, I wonder if it is possible with this technology?

    Seems limited to things that are made up primarily of the same types of atoms?

    I wonder if you could do this with sound waves, (or with this tech) kind of like how noise cancelling tech works, but tuned to the water in food/drink, if you specifically shot the slight or sound waves at the frequency of water (OR H or O atoms instead) molecules to steady them it would theo

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