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Researchers Chill Mirror to Near Absolute Zero

Posted by samzenpus on from the barely-moving dept.

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."

20 of 202 comments (clear)

  1. Mirror by biocute · · Score: 5, Interesting

    What's the significance of chilling a dime-sized mirror, vs chilling a dime?

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    1. Re:Mirror by glwtta · · Score: 5, Funny

      Makes you look cool?

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  2. Re:This is cool stuff and all... by camperdave · · Score: 4, Funny

    could someone explain what the significance of this is?

    Perhaps we could reflect on it.

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  3. Re:This is cool stuff and all... by sholden · · Score: 3, Informative

    You could try reading the first sentence of the article.

  4. I imagine that by pavon · · Score: 5, Informative

    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.

  5. Confirms quantum theory by quokkapox · · Score: 4, Informative

    It confirms our understanding of light and matter and how they interact. You would think that shining light (energy) on something would warm it up. If it cools it down, something strange is going on.

    In a broader sense, it means that we can manipulate matter and energy in ways nobody imagined 100 years ago (well, except for Einstein).

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    1. Re:Confirms quantum theory by Anonymous Coward · · Score: 5, Insightful

      It confirms our understanding of light and matter and how they interact. You would think that shining light (energy) on something would warm it up. If it cools it down, something strange is going on. You must not be familiar with how waves interact. The light waves and the material's "atom waves" are interacting so that maximum destructive interference is achieved; same frequency but half a wavelength out of phase of each other. The resulting wave of the atoms in the material should then have close to zero energy because other waves in the system may add constructively interfere with the atom waves.

      In my opinion, scientists may be able to approach absolute zero but they will never effectively reach it. They may hit a point at which it can be proclaimed as "good enough", but since the entire system must contain no energy and energy will always leak into the system from the universe, absolute zero will not be reached in actuality.

      The benefits of moving closer to absolute zero are that we can better understand exactly what atoms do when macro-forces are canceled out and only micro-forces apply, how the building blocks relate to each other in an energy-less environment, and if any other "laws" apply to our universe that we just weren't able to witness otherwise.
    2. Re:Confirms quantum theory by NightHwk1 · · Score: 4, Informative

      It seems like it's the same effect as noise cancellation... firing pulses at the exact opposite frequency of the atom.

      And about the mirror versus using an actual dime or something else--a perfectly smooth, very thin object probably makes atomic-level laser targeting much easier than a relatively rough object such as a coin.

    3. Re:Confirms quantum theory by tomatensaft · · Score: 4, Informative

      There is no such thing as opposite frequency. There is a thing like counterphase, though. So, noise cancellation works by emitting noise of the same frequency, but in a counterphase.

    4. Re:Confirms quantum theory by growse · · Score: 3, Informative

      You are correct, and I believe GP is wrong to assume that matter at absolute zero has no energy. It actually has whatever the zero-point energy is (for it's particles), which all quantum physics and wikipedia-browsers will know is the expectation value of the Hamiltonian :)

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  6. I thought this was a breakthrough by Barkmullz · · Score: 5, Informative

    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.

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    1. Re:I thought this was a breakthrough by btgreat · · Score: 4, Informative

      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)).

  7. Here's the sginificance. by deft · · Score: 5, Funny

    The real world application of this will be truly shown when they find the exact frequency on beer.

    Then, gaze upon its brilliance.

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  8. Re:This is cool stuff and all... by sarge+apone · · Score: 5, Funny

    could someone explain what the significance of this is?

    Perhaps we could reflect on it.

    Absolutely... to a degree.

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  9. That's nothing by edwardpickman · · Score: 5, Funny

    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.

  10. Re:This is cool stuff and all... by YGingras · · Score: 5, Interesting

    It has many applications in astronomy. During the winter, the only expedition to climb to the top of the Mauna Kea are to fill the liquid nitrogen and liquid helium tanks of those huge telescopes. We don't realize it but getting pretty picture in IR requires that you more of less shut down the black body radiation of your optics. With liquid helium they cool the CCDs to 4.5 Kelvin. They use so much of the stuff that they need to fill the tanks every other week. I admit that I have no idea how big is the said tank but laser cooling would open the way to mostly unattended (think orbital) telescopes for a much broader part of the spectrum. At the moment we send IR orbital scopes with big tanks of liquid helium which is dead lift weight that could be used for larger optics and we drop the scopes in the ocean when they run out of the stuff. Spitzer, unlike Hubble, will be useless soon and will not be able to perform observations even if all the mechanical and electronics are still in top condition. If you ever visit the Mauna Kea, notice the frost patches inside the observatory. It's kind of cold up there but the best experience is inside the observatory: it's freezing, everyone is dizzy after climbing the stair (the air is really thin) and you see all those big pipes with cryo-steam. It feels like the visit to the cryo chamber in Akira.

  11. Re:Thought of that once.... by SnowZero · · Score: 4, Funny

    I've heard that eating a mirror was bad luck.

    Nothing came up on Snopes.com, so it must be true...

  12. Re:Conservation of Energy... by smaddox · · Score: 3, Interesting

    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).
  13. Re:Conservation of Energy... by Engine · · Score: 3, Interesting

    You are correct. The scattered light is blue shifted due to the energy it takes away.

  14. Re:Obligatory Star Trek Refference by Mifflesticks · · Score: 3, Informative

    You realize that star trek reference (the star trek enterprise episode title) is itself a reference to Corinthians in the new testament, right? And that it's not the only time star trek has referenced it... another translation comes out not as "in a mirror darkly" but "through a glass, darkly", for the same passage, which Picard says in Star Trek Nemesis.

    Plus many books have used the same reference too.... but now I'm rambling.