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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."
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.
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.
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.
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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.