Featured Research

from universities, journals, and other organizations

Connecting the (quantum) dots: First viable high-speed quantum computer moves closer

Date:
February 26, 2013
Source:
University of Pittsburgh
Summary:
Scientists have developed a new method that better preserves the units necessary to power lightning-fast electronics, known as qubits. Hole spins, rather than electron spins, can keep quantum bits in the same physical state up to 10 times longer than before, the report finds.

This graphic displays spin qubits within a nanowire.
Credit: Image courtesy of University of Pittsburgh

Recent research offers a new spin on using nanoscale semiconductor structures to build faster computers and electronics. Literally.

University of Pittsburgh and Delft University of Technology researchers reveal in the Feb. 17 online issue of Nature Nanotechnology a new method that better preserves the units necessary to power lightning-fast electronics, known as qubits (pronounced CUE-bits). Hole spins, rather than electron spins, can keep quantum bits in the same physical state up to 10 times longer than before, the report finds.

"Previously, our group and others have used electron spins, but the problem was that they interacted with spins of nuclei, and therefore it was difficult to preserve the alignment and control of electron spins," said Sergey Frolov, assistant professor in the Department of Physics and Astronomy within Pitt's Kenneth P. Dietrich School of Arts and Sciences, who did the work as a postdoctoral fellow at Delft University of Technology in the Netherlands.

Whereas normal computing bits hold mathematical values of zero or one, quantum bits live in a hazy superposition of both states. It is this quality, said Frolov, which allows them to perform multiple calculations at once, offering exponential speed over classical computers. However, maintaining the qubit's state long enough to perform computation remains a long-standing challenge for physicists.

"To create a viable quantum computer, the demonstration of long-lived quantum bits, or qubits, is necessary," said Frolov. "With our work, we have gotten one step closer."

The holes within hole spins, Frolov explained, are literally empty spaces left when electrons are taken out. Using extremely thin filaments called InSb (indium antimonide) nanowires, the researchers created a transistor-like device that could transform the electrons into holes. They then precisely placed one hole in a nanoscale box called "a quantum dot" and controlled the spin of that hole using electric fields. This approach -- featuring nanoscale size and a higher density of devices on an electronic chip -- is far more advantageous than magnetic control, which has been typically employed until now, said Frolov.

"Our research shows that holes, or empty spaces, can make better spin qubits than electrons for future quantum computers."

"Spins are the smallest magnets in our universe. Our vision for a quantum computer is to connect thousands of spins, and now we know how to control a single spin," said Frolov. "In the future, we'd like to scale up this concept to include multiple qubits."


Story Source:

The above story is based on materials provided by University of Pittsburgh. Note: Materials may be edited for content and length.


Journal Reference:

  1. V. S. Pribiag, S. Nadj-Perge, S. M. Frolov, J. W. G. van den Berg, I. van Weperen, S. R. Plissard, E. P. A. M. Bakkers, L. P. Kouwenhoven. Electrical control of single hole spins in nanowire quantum dots. Nature Nanotechnology, 2013; DOI: 10.1038/nnano.2013.5

Cite This Page:

University of Pittsburgh. "Connecting the (quantum) dots: First viable high-speed quantum computer moves closer." ScienceDaily. ScienceDaily, 26 February 2013. <www.sciencedaily.com/releases/2013/02/130226114021.htm>.
University of Pittsburgh. (2013, February 26). Connecting the (quantum) dots: First viable high-speed quantum computer moves closer. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2013/02/130226114021.htm
University of Pittsburgh. "Connecting the (quantum) dots: First viable high-speed quantum computer moves closer." ScienceDaily. www.sciencedaily.com/releases/2013/02/130226114021.htm (accessed July 30, 2014).

Share This




More Computers & Math News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Twitter Earnings Blow Away Analysts' Predictions

Twitter Earnings Blow Away Analysts' Predictions

Newsy (July 29, 2014) After reporting a strong second quarter in both revenue and active monthly users, Twitter saw a big boost to its shares in after-hours trading. Video provided by Newsy
Powered by NewsLook.com
It's Not Just Facebook: OKCupid Experiments With Users Too

It's Not Just Facebook: OKCupid Experiments With Users Too

Newsy (July 29, 2014) If you've been looking for love online, there's a chance somebody has been looking at how you're looking. Video provided by Newsy
Powered by NewsLook.com
Why Facebook Wants You To Download Its Messenger App

Why Facebook Wants You To Download Its Messenger App

Newsy (July 29, 2014) Facebook will start requiring users to download a separate Messenger application if they wish to continue using Facebook for mobile messaging. Video provided by Newsy
Powered by NewsLook.com
Teen's Phone Ignites Under Her Pillow; How Real Is The Risk?

Teen's Phone Ignites Under Her Pillow; How Real Is The Risk?

Newsy (July 28, 2014) A Texas teen's Samsung phone apparently ignited while she slept, but what was the real problem here? Video provided by Newsy
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:
from the past week

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