Featured Research

from universities, journals, and other organizations

Energy Needs May Limit Size, Ability Of Quantum Computers

Date:
November 28, 2002
Source:
University Of Arkansas, Fayetteville
Summary:
The energy required to create an accurate quantum computer may limit the ability of scientists to make these novel devices small, fast, cheap and efficient, says a University of Arkansas researcher. Julio Gea-Banacloche, professor of physics, found that the more accuracy you want, the more energy you need. He reports his findings in a recent issue of Physical Review Letters.

FAYETTEVILLE, Ark. — The energy required to create an accurate quantum computer may limit the ability of scientists to make these novel devices small, fast, cheap and efficient, says a University of Arkansas researcher.

Related Articles


Julio Gea-Banacloche, professor of physics, found that the more accuracy you want, the more energy you need. He reports his findings in a recent issue of Physical Review Letters.

Quantum computing relies on using single atomic particles as units for information storage. Manipulating this information requires pulsed electromagnetic fields—which contain energy.

"The question of where this energy is going to come from and where it is going to go has to be addressed," he said. "Also, with solid-state controllers, such as capacitors, there is a minimum size because they have to be able to hold a certain amount of energy."

Gea-Banacloche wanted to determine whether there was a minimum amount of energy required for such quantum operations and if this has an impact on how well quantum computers perform.

He found that the energy needed to perform a calculation is inversely proportional to the error rate: In other words, more energy means less uncertainty.

"The more precise you want to be, the more energy you need to put into the system," he said.

Gea-Banacloche began to explore different types of proposed quantum computing control systems—including atom-to-atom interactions and electromagnetic fields—and found the same energy requirements in all of them.

"That is when I began to suspect there was some kind of underlying principle operating here," he said. "Ultimately, it all comes from Heisenberg’s Uncertainty Principle." This principle states that the more precisely the position of a particle is determined, the less precisely the momentum is know in this instant, and vice versa.

Quantum computers have a property called decoherence time—a time limit for operating before the system falls apart. Shorter decoherence times require a higher energy expenditure. Gea-Banacloche’s estimate of the minimum power requirement of a system with a ten microsecond decoherence time is 10 megaWatts. Most solid state quantum systems—systems built of atoms in a solid matrix—currently operate with even shorter decoherence times. Atomic trap quantum devices, which use electric and magnetic forces to hold atoms in place, have longer decoherence times.

"It’s not an impossibility, but it’s an indication of how important it is to improve the decoherence times and improve error correction," he said.

Accuracy matters to all computer users—and especially to researchers who rely on them to compute, store and retrieve data. But in the quantum computing world errors will occur unless something is done to prevent them. Quantum computers must constantly scan and correct every bit for errors because of the decoherence property—the tendency for a system to fall apart. If you have a device with a million bits of information, bursts of energy must be sent to all of the bits, all at once, all the time, to correct for errors. Devices with short decoherence times must perform these operations more often. So small margins of error require large amounts of energy.

"If you could come up with a way to tolerate more error, there could be a big payoff," Gea-Banacloche said.


Story Source:

The above story is based on materials provided by University Of Arkansas, Fayetteville. Note: Materials may be edited for content and length.


Cite This Page:

University Of Arkansas, Fayetteville. "Energy Needs May Limit Size, Ability Of Quantum Computers." ScienceDaily. ScienceDaily, 28 November 2002. <www.sciencedaily.com/releases/2002/11/021126203508.htm>.
University Of Arkansas, Fayetteville. (2002, November 28). Energy Needs May Limit Size, Ability Of Quantum Computers. ScienceDaily. Retrieved January 25, 2015 from www.sciencedaily.com/releases/2002/11/021126203508.htm
University Of Arkansas, Fayetteville. "Energy Needs May Limit Size, Ability Of Quantum Computers." ScienceDaily. www.sciencedaily.com/releases/2002/11/021126203508.htm (accessed January 25, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Sunday, January 25, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NTSB: Missing Planes' Black Boxes Should Transmit Wirelessly

NTSB: Missing Planes' Black Boxes Should Transmit Wirelessly

Newsy (Jan. 23, 2015) In light of high-profile plane disappearances in the past year, the NTSB has called for changes to make finding missing aircraft easier. Video provided by Newsy
Powered by NewsLook.com
Iconic Metal Toy Meccano Goes Robotic

Iconic Metal Toy Meccano Goes Robotic

Reuters - Innovations Video Online (Jan. 22, 2015) Classic children&apos;s toy Meccano has gone digital, releasing a programmable kit robot that can be controlled by voice recognition. The toymakers say Meccanoid G15 KS is easy to use and is compatible with existing Meccano pieces. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
The VueXL From VX1 Immersive Smartphone Headset!

The VueXL From VX1 Immersive Smartphone Headset!

Rumble (Jan. 22, 2015) The VueXL from VX1 is a product that you install your smartphone in and with the magic of magnification lenses, enlarges your smartphones screen so that it&apos;s like looking at a big screen TV. Check it out! Video provided by Rumble
Powered by NewsLook.com
Analysis: NTSB Wants Better Black Boxes

Analysis: NTSB Wants Better Black Boxes

AP (Jan. 22, 2015) NTSB investigators recommended Thursday that long-distance passenger planes carry improved technology to allow them to be found more easily in a crash, as well as include enhanced cockpit recording technology. (Jan. 22) Video provided by AP
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