Trapped, Imaged Single Atoms May Enable Powerful Quantum Computing

July 20, 2007 By Laura Mgrdichian feature
Trapped, Imaged Single Atoms May Enable Powerful Quantum Computing

An image of one plane of the cubic atom array. Bright spots are single atoms; the haze is from atoms trapped in out-of-focus planes.

Quantum computers have the potential to vastly out-perform present-day “classical” computers – if scientists can identify and manipulate promising quantum bits, or “qubits,” the basic information-storing units of a quantum computer.

Recently, researchers from The Pennsylvania State University trapped and imaged a three-dimensional array of 250 neutral atoms – each a promising qubit. This work could one day form the base for an incredibly powerful quantum computer.

“Atoms are ideal quantum systems,” explains Penn State physicist David Weiss, the experiment's corresponding scientist, to PhysOrg.com. “We have shown that we can trap hundreds of isolated atoms in such a way that it should be possible to individually address them, making each of them a qubit. It may be a long road from here to a useful quantum computer, but we can already see quite far down that road.”

Weiss and his group, including postdoctoral researcher Karl Nelson and graduate student Xiao Li, who performed the work, say that a quantum computer consisting of even 50 qubits could perform simulations way beyond those of current computers. Prior to their work, however, fewer than ten atoms had been imaged simultaneously nor had scientists successfully used light to trap and image either single atoms or atom bunches into three-dimensional “optical lattices.”

The optical lattice this research group created results from three overlapping laser-beam pairs and traps cold neutral cesium atoms. The beams restrict the atoms tightly in all three directions and lock them into a cubic array, with equal spacing between each atom. This occurs due to the interference pattern produced by the crossed beams; that is, how the light waves add and cancel each other, resulting in a regular cubic grid of maxima (bright spots) and minima (dark spots). The atoms are trapped in the minima.

Weiss and his colleagues imaged the lattice plane by plane, taking photographs of each layer. The photos show that the light used to image the array is highly unlikely to cause atoms to hop around in the lattice, a requirement if this type of atom arrangement could be one day used in a quantum computer. The researchers also assert that the spacing between each atom should be large enough such that individual atoms can be manipulated. By combining this ability with the ability to repeatedly image the array without disrupting it, the scientists think they have the basic ingredients for workable qubits. Their method could be used to create optical lattices containing thousands of atoms.

However, warns Weiss, “I don't want to understate the technical challenge of building a large quantum computer with our approach, or any other approach.”

Citation: Karl D. Nelson, Xiao Li and David S. Weiss, “Imaging single atoms in a three-dimensional array.” Nature Physics advance online publication DOI:10.1038/nphys645

Copyright 2007 PhysOrg.com.
All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.

4.5 /5 (61 votes)  

Rank 4.5 /5 (61 votes)
Tags

Relevant PhysicsForums posts

More news stories

Explained: Sigma

It's a question that arises with virtually every major new finding in science or medicine: What makes a result reliable enough to be taken seriously? The answer has to do with statistical significance -- but ...

Physics / General Physics

created Feb 09, 2012 | popularity 5 / 5 (19) | comments 76

Quantum physicist explains $100K offer for proof scaled-up quantum computing is impossible

(PhysOrg.com) -- MIT researcher Scott Aaronson has certainly riled the physics community with his offer this past Friday, of $100,000 to anyone who can prove that scaled-up quantum computing is impossible. ...

Physics / Quantum Physics

created Feb 08, 2012 | popularity 4.2 / 5 (13) | comments 35 | with audio podcast weblog

Diamond light, brighter than the sun

It’s the size of five football pitches and generates light 10 billion times brighter than the sun. As the Diamond Light Source celebrates its tenth anniversary this year, Penny Bailey visits one of the ...

Physics / General Physics

created Feb 07, 2012 | popularity 4.3 / 5 (7) | comments 18 | with audio podcast

Physicists 'record' magnetic breakthrough

An international team of scientists has demonstrated a revolutionary new way of magnetic recording which will allow information to be processed hundreds of times faster than by current hard drive technology.

Physics / General Physics

created Feb 07, 2012 | popularity 4.5 / 5 (41) | comments 14 | with audio podcast

Hints of the Higgs - papers are submitted

Back in December 2011, the ATLAS and CMS experiments at CERN presented some exciting results that provided tantalising hints of the Higgs boson.

Physics / General Physics

created Feb 08, 2012 | popularity 4.1 / 5 (7) | comments 10


Injured boomers beware: Know when to see doctor

(AP) -- It happened to nurse Jane Byron years after an in-line skating fall, business owner Haralee Weintraub while doing "men's" push-ups, and avid cyclist Gene Wilberg while lifting a heavy box.

Google might launch Drive for cloud storage soon

(PhysOrg.com) -- Google's next big move, according to the Wall Street Journal, is a cloud storage service called Drive. Hardly first to the plate, Google is simply catching up to introducing its cloud reposi ...

Latin America mining boom clashes with conservation

Latin America is experiencing a mining boom as prices rise fuelled by a hike in global demand, but the region is also being hit by a wave of violent protests, strikes and rallies by environmentalists.

Love a click away in Indonesia's Twitter Republic

He was a geeky kid from Yogyakarta, she a glamorous city girl in Jakarta. In a country with one of the world's most vibrant social networking scenes they fell in love on Twitter.

Europeans protest controversial Internet pact

Tens of thousands of people marched in protests in more than a dozen European cities Saturday against a controversial anti-online piracy pact that critics say could curtail Internet freedom.

Walney offshore wind farm is world's biggest (for now)

(PhysOrg.com) -- The Walney wind farm on the Irish Sea--characterized by high tides, waves and windy weather--officially opened this week. The farm is treated in the press as a very big deal as the Walney ...