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Scientists Using Lasers To Cool Molecules
An anonymous reader writes "Ever since audiences heard Goldfinger utter the famous line, 'No, Mr. Bond; I expect you to die,' as a laser beam inched its way toward James Bond and threatened to cut him in half, lasers have been thought of as white-hot beams of intensely focused energy capable of burning through anything in their path. Now a team of Yale physicists has used lasers for a completely different purpose, employing them to cool molecules down to temperatures near absolute zero, about -460 degrees Fahrenheit. Their new method for laser cooling, described in the online edition of the journal Nature, is a significant step toward the ultimate goal of using individual molecules as information bits in quantum computing."
.. with friggin' freeze rays on their heads .... *groan*
Laser cooling has been used for quite some time. What's the story here? The temperature?
The difference here is that they have used it to cool molecules. Up to now, only atoms have been cooled using this method.
If it weren't for deadlines, nothing would be late.
What about human readable units for once? maybe 1 Kelvin or -272C would be OK
Laser beams are focused energy in the form of electromagnetic radiation, not energy in the form of thermal entropy of molecules in matter. There is a difference. Laser beams can transmit their heat to matter (they normally do), but laser beams are not "Hot".
Just because I can hook a shark from a boat, I do no offer to wrestle it in the water.
Wrong. Laser beams are very cold. The photons are highly ordered and there is very little random motion among them.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Who the hell uses Fahrenheit for anything remotely connected to science? I can understand translating 0K to -273.15C, then 1K is -272.15C -- but how meaningful to anyone is -459.67F?
Ian Ameline
They may have a new method, but laser cooling itself is not new. There was even a Nobel prize awarded in 1997. It seems the advancement here is that they are using laser cooling on molecules (strontium monofluoride) instead of single atoms.
lasers have been thought of as white-hot beams of intensely focused energy
If there is anything that lasers are not, it's white.
Proud member of the Weirdo-American community.
Come on. Just say 0 K.
Acknowledging the appropriate SI units only stings for a little while.
If memory serves, the heat of a group of atoms is based both on their kinetic energy and vibrational energy. In gasses and, to a lesser extent, liquids, the average velocities of atoms is one factor determining factor of how much heat is in the gas or liquid, but so is the vibrational energy of the atom (otherwise solids wouldn't be capable of getting hot, which they clearly can).
So while these scientists have demonstrated being able to reduce the kinetic energy of an atom to zero, the article says nothing about being able to do so for its vibrational energy. It seems very possible that hitting an atom with lasers may be able to reduce its kinetic energy but may, depending on the frequency of light used, actually increase its vibrational energy.
So, this approach may work fine for gasses, in which certain atoms can be made motionless and, as long as you keep other atoms from interacting with them, they never pass on their vibrational energy, and thus can be seen as being very cold. But it's hard to see how such an approach has much merit for atoms in liquids or solids.
Wrong. Laser beams are very cold. The photons are highly ordered and there is very little random motion among them.
Wrong? It's not true that the general Bond-watching audience thinks of lasers as being white hot?
Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
Shooting things with laser until they stop moving cools them? I guess its for more than cooking now.
When I shot the neighbor's cat, with my CO2 laser, until it stopped moving, it cooled down. It dropped from 101.5 degrees F, to about 63 degrees F (ambient temperature at the coolest part of that night) . It took several hours, but it cooled down.
[disclaimer] The above statement was purely jest. I have never shot anything with a laser, and have never intentionally harmed an animal. Any agency that is sniffing my packets will not find the stench of wrongdoing here. Just the stench of a bad joke.
No, Mr. Bond; I expect you to yell like a little girl while I am freezing your balls!
You can't handle the truth.
This is why I read /. I saw the headline, remembered trying to explain laser cooling to my Dad 10 years ago, and cam here to post that it was old news. The first thing I see however is your post telling me exactly what's going on. Thank you ClickOnThis for saving me time and frustration.
Is 1563649 a prime number?
Wrong? It's not true that the general Bond-watching audience thinks of lasers as being white hot?
It's pretty obvious: The atoms are stirred, not shaken.
http://lmgtfy.com/?q=What%27s+the+difference+between+an+atom+and+a+molecule
This is a particularly bad science article. First of all, this research is interesting because they are laser cooling molecules. The article makes it sound like the new thing here is using lasers to cool. Laser cooling of atoms has been around for decades, but laser cooling of molecules is considerably more difficult because molecules have far more resonant transitions than do atoms (this is due to the additional rotational and vibrational degrees of freedom.) Traditional Doppler laser cooling relies on cycling transitions, in which the atoms go back and forth between two levels, losing momentum as they cycle. If the particles can "escape" to other levels, the cycle breaks and cooling stops. Traditionally, in atoms this problem is solved by having other lasers on the table which "plug up" these holes by repumping the atoms back into the cooling cycle. With molecules, there has historically been far too many holes to simply plug them with other lasers.
Second, Fahrenheit? Seriously? Nano/Micro/MilliKelvin is the appropriate unit.
Yeah, you hold your breath until that happens.
The Kruger Dunning explains most post on
You know, I have one simple request. And that is to have sharks with frickin' laser beams attached to their heads!
...and five missiles, we can finally kill a Metroid.