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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."

6 of 202 comments (clear)

  1. 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.

  2. 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 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.

    2. 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.

  3. 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)).