New type of light interaction with atoms allows for manipulating cloud shape

October 24, 2017 by Bob Yirka, report
New type of light interaction with atoms allows for manipulating cloud shape
Credit: Physical Review Letters (2017). DOI: 10.1103/PhysRevLett.119.163201

A team of researchers at the Weizmann Institute of Science in Israel has found a new way to manipulate atoms using light. In their paper published in Physical Review Letters, the team describes the new technique and possible uses for it.

Up until now, scientists have used two main techniques to manipulate with . The first involves firing a at a single atom to change its momentum. The other has been to cause an atom to "feel" an electric field force associated with a beam of light. Now, researchers have developed a third technique—one that involves firing a laser at an atom cloud.

The experiments involved creating a spherical cloud consisting of nothing but millions of cold rubidium-87 atoms. The researchers then fired a pulse of infrared light at the cloud (the frequency was described as "far detuned" from rubidium-87 transitions) and found the cloud responded by behaving similarly to a lens, deflecting the light and causing the cloud to become longer and thinner—the light beam essentially squished the sphere into a new shape. The researchers note that the parameters of the beam they fired at the cloud had been idealized to reduce the force between the light's electric field and the individual rubidium atoms.

The researchers suggest the change in cloud shape resulted from the collective effect of the laser acting on all of the atoms in the cloud—conservation of momentum caused the atoms to respond to a force pushing against them in a direction opposite the deflection. The team has invented a term to describe the overall effect: electrostriction. They note that they ran their experiments on booth Bose-Einstein condensates and at higher temperatures.

Because it is a global optical , the researchers note, it could be easily modified to allow for easy tuning of interactions with lasers—an improvement over the current cumbersome method. They suggest their technique might prove useful in future cold atom experiments because it allows inducing interparticle interactions that can be easily turned.

Explore further: Proposed method to cause an atom to emit the same light as another atom

More information: Noam Matzliah et al. Observation of Optomechanical Strain in a Cold Atomic Cloud, Physical Review Letters (2017). DOI: 10.1103/PhysRevLett.119.163201

Related Stories

'Tornadoes' are transferred from light to sodium atoms

November 9, 2006

For the first time, tornado-like rotational motions have been transferred from light to atoms in a controlled way at the National Institute of Standards and Technology. The new quantum physics technique can be used to manipulate ...

NIST's compact gyroscope may turn heads

August 23, 2016

Shrink rays may exist only in science fiction, but similar effects are at work in the real world at the National Institute of Standards and Technology (NIST).

Laser cooling a polyatomic molecule

April 26, 2017

(—A team of researchers at Harvard University has successfully cooled a three-atom molecule down to near absolute zero for the first time. In their paper published in Physical Review Letters, the team describes ...

Scientists set traps for atoms with single-particle precision

November 3, 2016

Atoms, photons, and other quantum particles are often capricious and finicky by nature; very rarely at a standstill, they often collide with others of their kind. But if such particles can be individually corralled and controlled ...

Recommended for you

The hunt for leptoquarks is on

September 19, 2018

Matter is made of elementary particles, and the Standard Model of particle physics states that these particles occur in two families: leptons (such as electrons and neutrinos) and quarks (which make up protons and neutrons). ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Oct 25, 2017
So what was the force if not the electric field? How was the momentum transferred?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.