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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."

4 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?

    --
    Virtual Betting on Facebook for non-geeks.
  2. 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.

  3. 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).
  4. 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.