Featured Research

from universities, journals, and other organizations

Physicists have chilled the world's coolest molecule

Date:
August 21, 2014
Source:
Yale University
Summary:
Physicists have chilled the world's coolest molecules. The tiny titans in question are bits of strontium monofluoride, dropped to 2.5 thousandths of a degree above absolute zero through a laser cooling and isolating process called magneto-optical trapping. They are the coldest molecules ever achieved through direct cooling, and they represent a physics milestone likely to prompt new research in areas ranging from quantum chemistry to tests of the most basic theories in particle physics.

An optical cavity used to control the wavelength of some of the lasers used for the magneto-optical trap.
Credit: Photo by Michael Helfenbein

It's official. Yale physicists have chilled the world's coolest molecules.

The tiny titans in question are bits of strontium monofluoride, dropped to 2.5 thousandths of a degree above absolute zero through a laser cooling and isolating process called magneto-optical trapping (MOT). They are the coldest molecules ever achieved through direct cooling, and they represent a physics milestone likely to prompt new research in areas ranging from quantum chemistry to tests of the most basic theories in particle physics.

"We can start studying chemical reactions that are happening at very near to absolute zero," said Dave DeMille, a Yale physics professor and principal investigator. "We have a chance to learn about fundamental chemical mechanisms."

The research is published this week in the journal Nature.

Magneto-optical trapping has become ubiquitous among atomic physicists in the past generation -- but only at the single-atom level. The technology uses lasers to simultaneously cool particles and hold them in place. "Imagine having a shallow bowl with a little molasses in it," DeMille explained. "If you roll some balls into the bowl, they will slow down and accumulate at the bottom. For our experiment, the molecules are like the balls and the bowl with molasses is created via laser beams and magnetic fields."

Until now, the complicated vibrations and rotations of molecules proved too difficult for such trapping. The Yale team's unique approach drew inspiration from a relatively obscure, 1990s research paper that described MOT-type results in a situation where the usual cooling and trapping conditions were not met.

DeMille and his colleagues built their own apparatus in a basement lab. It is an elaborate, multi-level tangle of wires, computers, electrical components, tabletop mirrors, and a cryogenic refrigeration unit. The process uses a dozen lasers, each with a wavelength controlled to the ninth decimal point.

"If you wanted to put a picture of something high-tech in the dictionary, this is what it might look like," DeMille said. "It's deeply orderly, but with a bit of chaos."

It works this way: Pulses of strontium monofluoride (SrF) shoot out from a cryogenic chamber to form a beam of molecules, which is slowed by pushing on it with a laser. "It's like trying to slow down a bowling ball with ping pong balls," DeMille explained. "You have to do it fast and do it a lot of times." The slowed molecules enter a specially-shaped magnetic field, where opposing laser beams pass through the center of the field, along three perpendicular axes. This is where the molecules become trapped.

"Quantum mechanics allows us to both cool things down and apply force that leaves the molecules levitating in an almost perfect vacuum," DeMille said.

The Yale team chose SrF for its structural simplicity -- it has effectively just one electron that orbits around the entire molecule. "We thought it would be best to start applying this technique with a simple diatomic molecule," DeMille said.

The discovery opens the door for further experimentation into everything from precision measurement and quantum simulation to ultracold chemistry and tests of the standard model of particle physics.

The lead author of the paper is John Barry, a former Yale graduate student now at the Harvard-Smithsonian Center for Astrophysics. Other authors of the paper are Yale postdoctoral fellow Danny McCarron and graduate students Eric Norrgard and Matt Steinecker.


Story Source:

The above story is based on materials provided by Yale University. The original article was written by Jim Shelton. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. F. Barry, D. J. McCarron, E. B. Norrgard, M. H. Steinecker, D. DeMille. Magneto-optical trapping of a diatomic molecule. Nature, 2014; 512 (7514): 286 DOI: 10.1038/nature13634

Cite This Page:

Yale University. "Physicists have chilled the world's coolest molecule." ScienceDaily. ScienceDaily, 21 August 2014. <www.sciencedaily.com/releases/2014/08/140821115924.htm>.
Yale University. (2014, August 21). Physicists have chilled the world's coolest molecule. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2014/08/140821115924.htm
Yale University. "Physicists have chilled the world's coolest molecule." ScienceDaily. www.sciencedaily.com/releases/2014/08/140821115924.htm (accessed October 20, 2014).

Share This



More Matter & Energy News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Would A Travel Ban Even Work In Stopping Ebola Spread?

Would A Travel Ban Even Work In Stopping Ebola Spread?

Newsy (Oct. 19, 2014) The U.S. currently isn't banning travel from Ebola-stricken areas, but it's at least being considered. Some argue though it could be counterproductive. Video provided by Newsy
Powered by NewsLook.com
Tech Giants Push Back After FBI Suggests Less Encryption

Tech Giants Push Back After FBI Suggests Less Encryption

Newsy (Oct. 19, 2014) FBI Director James Comey's stance on encryption technology isn't receiving much support from the tech community. Video provided by Newsy
Powered by NewsLook.com
Microneedle Patch Promises Painless Pricks

Microneedle Patch Promises Painless Pricks

Reuters - Innovations Video Online (Oct. 18, 2014) Researchers at The National University of Singapore have invented a new microneedle patch that could offer a faster and less painful delivery of drugs such as insulin and painkillers. Video provided by Reuters
Powered by NewsLook.com
Cheap Oil: Good For Manufacturers, Bad For Many Economies

Cheap Oil: Good For Manufacturers, Bad For Many Economies

Newsy (Oct. 18, 2014) Oil prices dipped below $85 a barrel this week. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins