Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Trapping giant Rydberg atoms for faster quantum computers

07.05.2010
In an achievement that could help enable fast quantum computers, University of Michigan physicists have built a better Rydberg atom trap. Rydberg atoms are highly excited, nearly-ionized giants that can be thousands of times larger than their ground-state counterparts.

As a result of their size, interactions between Rydberg atoms can be roughly a million times stronger than between regular atoms. This is why they could serve as faster quantum circuits, said Georg Raithel, associate chair and professor in the Department of Physics. Quantum computers could solve problems too complicated for conventional computers. Many scientists believe that the future of computation lies in the quantum realm.

A paper on this research is published in the current edition of Physical Review Letters. The work will be presented at the American Physical Society's Division of Atomic, Molecular and Optical Physics meeting in late May.

Raithel's team trapped the atoms in what's called an optical lattice—a crate made of interfering laser beams.

"The optical lattice is better than any other Rydberg atom trap for quantum information processing or high-precision spectroscopy," Raithel said. "Compared with other traps, optical lattices minimize energy level shifts in the atoms, which is important for these applications."

Raithel and physics doctoral students Kelly Younge and Sarah Anderson started with ground-state atoms of the soft metal rubidium. At room temperature, the atoms whiz around at the speed of sound, about 300 meters per second. The researchers hit them with lasers to cool and slow them to 10 centimeters per second.

"That's about the speed of a mosquito," Younge said. "Cooling lasers combined with a magnetic field allows us to trap the ground-state atoms. Then we excite the atoms into Rydberg states."

In a rubidium atom, just one electron occupies the outer valence shell. With precisely tuned lasers, the researchers excited this electron so that it moved 100 times farther away from the nucleus of the atom, which classified it as a Rydberg atom. That valence electron in this case is so far away from the nucleus that it behaves almost as if it's a free electron.

To trap the Rydberg atoms, the researchers took advantage of what's called the "ponderomotive force" that allows them to secure a whole atom by holding fast to one electron—the sole valence shell particle in the rubidium Rydberg atoms. The optical lattice, formed with intense, interfering laser beams, is what provides the ponderomotive force.

"The laser field holds on to the electron, which behaves almost as if it were free, but the residual weak atomic binding force still holds the atom together. In effect, the entire atom is trapped by the lasers," Raithel said.

The physicists used a technique called "microwave spectroscopy," to determine how the lattice affected the Rydberg atoms, and in general how the atoms behaved in the trap.

"Essentially, we could track the motion of the atoms during the experiment. We could tell if the atoms were sitting in the bottom of a well in the electromagnetic field, or if they were roaming over many wells. In this way, we could optimize the performance of the trap," Younge said.

The paper is called "State-dependent Energy Shifts of Rydberg Atoms in a Ponderomotive Optical Lattice."

This research is funded by the National Science Foundation and the National Defense Science and Engineering Graduate Fellowship Program.

Contact: Nicole Casal Moore
Phone: (734) 647-7087
Or
Contact: Carol Rabuck
Phone: (734) 763-2588

Nicole Casal Moore | EurekAlert!
Further information:
http://www.umich.edu

Further reports about: Science TV Trapping laser beam magnetic field optical data optical lattice

More articles from Physics and Astronomy:

nachricht Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich

nachricht Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>