Physicists in New Zealand say they've advanced quantum technology, creating "optical tweezers" that can be steered, using the unit's powerful laser to split clouds of atoms and then smash them into each other.
The researchers from the University of Otago wanted to better understand the way ultracold atoms -- at temperatures within a millionth or less of a degree of absolute zero -- interact with each other.
Writing in the U.S. journal Optics Letters, they've described their success splitting a cloud of ultracold rubidium atoms, creating 32 small "daughter" clouds.
In addition to splitting the clouds of atoms, the "optical tweezer" system allows the scientists to then collide them for further study.
"Tongue-in-cheek, we like to refer to our setup as the 'Littlest Hadron Collider,'" Otago lead researcher Niels Kjaergaard says.
"In some ways, it's the complete opposite of what is the world's largest and most powerful particle collider, because instead of using extreme acceleration, we smash our atom clouds together at a pedestrian pace of up to a metre per second," he says.
The system utilizes vertical and horizontal laser beams that are steered to confine and move atoms using precisely controlled traveling acoustic waves.
The laser beams can provide either an attraction or repulsion force on the atoms.
"This sort of precise control of these atoms is like being able to pull a delicate snowflake into two clean halves with your bare hands," Kjaergaard says. "It's quite remarkable that we are able to manipulate such minute and fragile samples while moving them such a comparatively large distance."
Two students in Kjaergaard's researcher group contributed to the system; Kris Roberts constructed the steerable optical tweezers as part of a thesis project, while Thomas McKellar, a graduate student, put together the acoustic wave control system.
"For researchers who are still students, these are quite notable achievements and I'm very proud of their work," Kjaergaard says.
Potential applications for the "tweezer" system could include new tools for examining microscopic structures or in sensors to map minute variations in magnetic fields.
The possibility of using lasers as optical "tweezers" for atomic-level manipulation was first put forward in 1970.
Some researchers have used optical tweezers in recent years to study biological systems at the molecular and atomic level.
