Scientists Using Lasers To Cool Molecules 169
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."
Re:Laser cooling? (Score:5, Informative)
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.
Energy, not heat. (Score:5, Informative)
News from 1978 (Score:1, Informative)
http://lmgtfy.com/?q=laser+cooling
http://en.wikipedia.org/wiki/Laser_cooling
"...lasers have been thought of as white-hot..." (Score:5, Informative)
Laser cooling is not new... (Score:5, Informative)
They may have a new method, but laser cooling [wikipedia.org] itself is not new. There was even a Nobel prize [nobelprize.org] awarded in 1997. It seems the advancement here is that they are using laser cooling on molecules (strontium monofluoride) instead of single atoms.
Well, that's clueless for you (Score:5, Informative)
lasers have been thought of as white-hot beams of intensely focused energy
If there is anything that lasers are not, it's white.
Re:Who the hell... (Score:2, Informative)
Who the hell uses Fahrenheit for anything remotely connected to science?
I know, they should have totally used Rankine. [wikipedia.org]
Re:Well, that's clueless for you (Score:3, Informative)
Re:Farenheit? (Score:3, Informative)
As someone who isn't American I can't even do that. My entire knowledge of Farenheit is that 0 C is around 32 F. and 451 F is where paper burns. Also the conversion rate is like TempInCelcius * (9/5) -32 or something. It's really a terrible system to use for a scienctific article.
ridiculous summary (Score:4, Informative)
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.
Re:Who the hell... (Score:3, Informative)
"Who the hell uses Fahrenheit for anything remotely connected to science?"
First and foremost, you write for your audience. If your intended audience typically uses degrees Fahrenheit, you use degrees Fahrenheit. That, or you triple the size of your article, with the bulk of it devoted to phrases like "triple point of water" that will make your audience's eyes glaze over.
Second, you're not going to do very well in a thermodynamics course in the United States (let alone get meaningful work afterward) if you can't handle degrees Rankine as well as kelvins. Much like writing for your audience, you work with the tools you have at hand, rather than insisting that someone rip out a perfectly good boiler simply because it wasn't built to SI specifications.
Finally, they already said "absolute zero," so you already have a perfectly valid thermodynamic temperature measurement. So long as they're using a US unit alongside it rather than instead of it, why do you care?
Re:Farenheit? (Score:3, Informative)
That's not true at all.
If you are doing heat transfer calculations in systems that use the Fahrenheit scale for measuring temperature then you absolutely need the Rankine scale.
There are plenty of real-world systems that measure boiler temperature and cooling water temperature in Fahrenheit.