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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?
.. with friggin' freeze rays on their heads .... *groan*
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.
Shooting things with laser until they stop moving cools them? I guess its for more than cooking now.
http://lmgtfy.com/?q=laser+cooling
http://en.wikipedia.org/wiki/Laser_cooling
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.
We now know that almost 40 years ago, UFO Space Aliens were shining beams of light into nuclear weapons storage areas to make them inoperable . Former USAF officers will be having a press conference on Friday, to prove it. So, big deal on the whole lasers-cooling-molecules thing.
Don't disappoint your bird dog. Go to the range.
Didn't scientists already cool molecules with a LASER? As far as I know, the frequency of the LASER-beam must be a little lower than the resonance-frequency of the atom/molecule so that by moving around through thermic energy the atom/molecule can absorb the beam with respect to doppler effect.
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.
What's wrong with just plain "absolute zero"? What's the point in adding "What's known as"? Why do science writers use this silly phrase?
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
2. old news
uggh
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
There is a PBS special called Absolute Zero that shows this. http://www.pbs.org/wgbh/nova/zero/atoms.html This is about the only way to create a Bose-Einstein condensate
What, no Mr. Freeze comments yet? Ice to see you!
"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,
It's obvious that this was doomed to failure from the very beginning. They forgot about the shark.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
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.
I want a laser cooled PC, water cooling can leak, air cooling is inefficient, I can't wait till this gets used in similar products
-Ours is the wisdom of Solomon, the magic of Merlyn, the fall of Icaris.
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.
Didn't Cohen-Tannoudji do this, like, a long time ago? Didn't he already get the nobel prize for it? I mean, the concept isn't like it is super-new stuff.
I always thought lasers were cool.
I don't wanna ask a mad scientist, Y'all got frikkin sharks...
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
No, Mr. Bond; I expect you to yell like a little girl while I am freezing your balls!
You can't handle the truth.
The general Bond-watching audience cannot reasonably be said to think at all.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
They should be using the lasers to freeze sharks so that we can have frozen sharks with frikken freezing lasers on their heads.
In Soviet Russia.
In Soviet Russia, shark laser freezes you!
I'll be honest, we're throwing science against the wall to see what sticks. -Cave Johnson
...Now i can really cool my bit to increase my download speed but not too much... the stream of bit will freeze :)
Now if only the scientists would use lasers to cool all the /. readers. Goddamn bunch o' nerds if you ask me.
So I guess you were watching a Bond film when you made that post and can thus be excused.
The enemies of Democracy are
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.
I thought the line "No, Mr. Bond, I expect you to die!" was related to coordinate substitution in a rotating frame, not lasers.
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?
Clearly we think of them as red-hot.
Actually I haven't seen Goldfinger in ages, but weren't the lasers red? Wouldn't it then be logical to think that the lasers are red-hot rather than white-hot?
This comment isn't quite pointless enough yet, so I'll throw in a, "wah! they should have used real units like celsius! wah!"
http://lmgtfy.com/?q=What%27s+the+difference+between+an+atom+and+a+molecule
Can an atom be split using extereme cold? If you stop all the motion of an atom due to absolute zero does it fall apart? Is absolute zero a cessation of motion on a molecular level or an atomic level?
I read Slashdot for the headlines, because the headlines, unlike the articles, are usually original and never duplicated
It wants its Nobel Prize back.
Seriously, laser cooling has been around for decades. Want a more interesting article? How about something about a laser which really is a beam of intensely-focused energy capable of burning through anything in its path? Especially if it runs on house current
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.
So if Dr. Evil put these freakin' laser beams on shark, then the shark would eventually freeze in its own tank? That is good for Austin Powers!
"Vibrational energy" is just an oscillation between kinetic energy and potential energy in an elastically bound object. A single atom in a vacuum cannot have vibrational energy at all since there is no force acting on it.
When you damp the vibration of a string, you are actually operating on it's kinetic energy. Each time it strikes your finger it loses a bit more kinetic energy and so the next cycle is weaker than the last.
and to think that all this time I thought the Jedi were using heat to cut body parts off. Now we might find out they were freezing them and the limbs were fracturing and dropping off. Who'd a thunk?
LoB
"Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
You are also wrong. Laser beams are neither hot nor cold. Those terms qualitatively describe temperature. Temperature, at least when used scientifically, refers to the average kinetic energy of mass particles within a given volume (as they bounce around). Electromagnetic radiation does not have a temperature.
You are also wrong! Blackbody radiation, for example, certainly has a temperature associated with it. I'm actually not sure how to think of the temperature of a laser (and I have put some thought towards it, and am studying in quantum optics in grad school). Even a weak laser can heat up a physical object, so it is quite hot. It comes from a lasing material that is at a negative temperature, so it could also have negative temperature. But as another poster pointed out, it has very low entropy. This leads me to think that a laser has negative zero temperature.
Freezing a smuggler who's too quick to jettison his cargo at the first sign of Imperials.
I swear to God...I swear to God! That is NOT how you treat your human!
You are also wrong.
Indeed, they were. The following statement made me scratch my head a bit:
The photons are highly ordered and there is very little random motion among them.
By that logic, light traveling through a perfect vacuum would also have a "temperature". Which is... well... puzzling.
-- Let us endeavor so to live that when we pass even the undertaker shall be sorry. -- M. Twain
I propose that any time anyone suggests that a given temperature scale is more "natural" or "arbitrary" than another temperature scale, they automatically lose the argument. And get perma-banned from Slashdot. These "my temperature scale can beat up your temperature scale" arguments are beyond tiresome.
You know, I have one simple request. And that is to have sharks with frickin' laser beams attached to their heads!
While you can infer the temperature of a blackbody from the radiation, the radiation itself does not have a temperature. And just because radiation can heat an object, does not mean the radiation itself has "heat". The radiation has energy... which when transfered to an object with mass results in that object heating up.
Temperature is a property that only applies to particles with mass. And really only applies to groups of particles. Hence heat (which is a more qualitative description of temperature or a change in temperature) only applies to particles with mass.
I don't think I agree with that. Let's say we have one system that is held at a fixed temperature, and another system that is isolated, other than a radiative connection to the first. Looking only at this second system, the only interaction it has is through this radiation field. It eventually assumes the same temperature as the first system. However, it's only "seeing" the radiation field. Therefore it's the radiation field that has that temperature.
For decades now the microwave has been a common kitchen appliance. But what good is a microwave when your beer is warm? It's about time someone came up with a rapid chilling system for beer. When can I expect to see one of these at Best Buy?
"Love is a familiar; Love is a devil: there is no evil angel but Love." --William Shakespeare ('Love's Labors Lost')
This is news for nerds. We all know what absolute zero is.
Let's say we have one system that is held at a fixed temperature, and another system that is isolated, other than a radiative connection to the first. Looking only at this second system, the only interaction it has is through this radiation field. It eventually assumes the same temperature as the first system. However, it's only "seeing" the radiation field. Therefore it's the radiation field that has that temperature.
Isn't that a bit like saying that a conveyor belt of negligible weight transporting 10000 tons of rocks from one location to another, one ton at a time, has significant weight itself? Kinetic energy in atoms is different from the energy of photons. As I understand it photons don't have temperature, they carry potential energy (momentum) which can be manifested in kinetic energy in matter it hits, but before it hits any matter this momentum is not temperature. When it hits the photon is converted to kinetic energy and ceases to exist. If I'm mistaken I'd love a clarification :)
Also, wouldn't a system (I'm assuming that it contains matter) that is completely isolated except for incoming radiation energy at a fixed level reach an arbitrarily high temperature given enough time?
Are you a grammar Nazi? I'm trying to improve my English; please correct my errors!
It gave me a huge cringe when I saw Fahrenheit. You are reporting a scientific news. Scientists don't use the non-standard British system.
...and five missiles, we can finally kill a Metroid.
I'm not sure physicists refer to photons as having potential or kinetic energy. Better to say they carry electromagnetic force.
But otherwise you are right, temperature is a measure of the kinetic energy of particles with mass. That energy can be converted to photons, which then radiate away until they are absorbed by other particles, which then heat up. None of that implies that photons have a temperature.
As far as your question goes, you can't stop a system from radiating, so at some level the outgoing radiation balances the incoming radiation and you reach a maximum temperature.
Are you really a physics grad student? Because that didn't make any sense.
A radiation field can carry energy between two systems. That does not mean it has a temperature. No more than an electric current has a temperature just because you can use it to heat your house.
Furthermore, I can disprove your example with one simple counter-example. The Earth is not the same temperature as the Sun. Both are isolated systems whose only manner of exchanging heat energy is through radiation. (Well, actually there's some energy moving around the system in particle flows, but that is not why the Earth is cooler than the Sun.)
Yes, but they aren't only exchanging radiation with each other. The Earth and Sun are constantly radiating to outer space, and would eventually assume the same temperature as the CMBR. If you set up a system that was only exchanging radiation with the Sun, and otherwise completely isolated, it would assume the temperature of the Sun. And there is no way you could possibly get hotter than that (via thermal coupling to the Sun).
This is really cool news I think.
Recipes for USA bankrupt - http://tinypaste.com/0d66f dd = dollar deluge (printed in the infinity)
Yes, and? The radiation itself is not defined as having any temperature, but merely wavelength, or more likely a spectrum of wavelengths. You could call the wavelength or frequency of photons "temperature", I guess, but nobody does that, because it would get really confusing. Temperature = movement of mass. Mass of photons = 0 (massless), ergo temperature of photons = undefined.
True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
http://www.lanl.gov/orgs/pa/science21/LaserCooling.html
For just one example.
The book Optical Refrigeration by Mansoor Sheik-Bahai and R.I. Epstein is an overview of this field that cools semiconductors and other macroscopic objects with lasers.
(disclaimer: I used to work as a grad student for Sheik-Bahai long ago. Very cool guy.)
Can i get one of those as my CPU cooler please?
There was an article 15 or so years ago in the Discover Magazine about lazer cooling. I remember a quote: that cooling elements with photons was like "trying to stop a freight train with a stream of ping-pong balls". The team in that article were working with gas suspended electromagnetically to help isolate the motion.