Featured Research

from universities, journals, and other organizations

Big step toward quantum computing: Efficient and tunable interface for quantum networks

Date:
May 23, 2012
Source:
University of Innsbruck
Summary:
Quantum computers may someday revolutionize the information world. But in order for quantum computers at distant locations to communicate with one another, they have to be linked together in a network. While several building blocks for a quantum computer have already been successfully tested in the laboratory, a network requires one additonal component: A reliable interface between computers and information channels. Austrian physicists now report the construction of an efficient and tunable interface for quantum networks.

At the core of the experiment lies an optical resonator consisting of two highly reflective mirrors.
Credit: C. Lackner

While several building blocks for a quantum computer have already been successfully tested in the laboratory, a network requires one additonal component: a reliable interface between computers and information channels. In the current issue of the journal Nature, physicists at the University of Innsbruck report the construction of an efficient and tunable interface for quantum networks.

Quantum technologies promise to redefine the landscape of information processing and communication. We already live in an information age, in which vast amounts of data are sent around the world over optical fibers, but future quantum networks may be many times more powerful. These networks will require interfaces that can transfer information from quantum processors onto light particles (photons). Such interfaces will allow optical fibers to transmit information-bearing photons between remote data registers, which are likely to be composed of quantum dots or ions.

In contrast to classical information, quantum information can't be copied without being corrupted. Instead, physicists around the world are searching for ways to transfer quantum information between matter and light using entanglement, the quantum property in which the state of one particle depends on the state of a second.

Now, a research team led by Rainer Blatt, Tracy Northup, and Andreas Stute at the University of Innsbruck's Institute for Experimental Physics has demonstrated the first interface between a single ion and a single photon that is both efficient and freely tunable.

High efficiency and precision

The Innsbruck physicists trap a single calcium ion in a so-called Paul trap and place it between two highly reflective mirrors. They excite the ion with a laser, thereby generating a photon which is entangled with the ion and which is reflected back and forth between the mirrors. Custom tuning of the entanglement between ion and photon is possible by adjusting the frequency and amplitude of the laser.

This technique has two significant advantages over previous approaches that have entangled atoms with light: "The efficiency with which we produce entangled photons is quite high and in principle could be increased to over 99 percent," explains Northup. "But above all, what this setup lets us do is generate any possible entangled state." To this end, the frequency and amplitude of the laser light are carefully chosen so that target collective state of the ion and photon is reached. At the core of the experiment lies an optical resonator consisting of two highly reflective mirrors. Photons bounce back and forth up to 25,000 times between these mirrors, interacting with the ion, before escaping through one mirror into an optical fiber. "Along with an efficient entanglement process, we've demonstrated an entangled quantum state between an atom and a photon with the highest precision measured to date," explains Andreas Stute.

Technology for the future

The experiment offers important insights into the interaction of light and matter and may prove useful in constructing quantum computers or a future quantum internet. "Whenever we have to transfer quantum information from processing sites to communication channels, and vice versa, we're going to need an interface between light and matter," explains Northup. The researchers are supported by the Austrian Science Fund (FWF) and the European Union.


Story Source:

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


Journal Reference:

  1. A. Stute, B. Casabone, P. Schindler, T. Monz, P. O. Schmidt, B. Brandstδtter, T. E. Northup, R. Blatt. Tunable ion–photon entanglement in an optical cavity. Nature, 2012; 485 (7399): 482 DOI: 10.1038/nature11120

Cite This Page:

University of Innsbruck. "Big step toward quantum computing: Efficient and tunable interface for quantum networks." ScienceDaily. ScienceDaily, 23 May 2012. <www.sciencedaily.com/releases/2012/05/120523135527.htm>.
University of Innsbruck. (2012, May 23). Big step toward quantum computing: Efficient and tunable interface for quantum networks. ScienceDaily. Retrieved April 21, 2014 from www.sciencedaily.com/releases/2012/05/120523135527.htm
University of Innsbruck. "Big step toward quantum computing: Efficient and tunable interface for quantum networks." ScienceDaily. www.sciencedaily.com/releases/2012/05/120523135527.htm (accessed April 21, 2014).

Share This



More Computers & Math News

Monday, April 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nintendo Changed Gaming World, but Its Future Uncertain: Upstone

Nintendo Changed Gaming World, but Its Future Uncertain: Upstone

AFP (Apr. 19, 2014) — The Nintendo Game Boy celebrates its 25th anniversary Monday and game expert Stephen Upstone says the console can be credited with creating a trend towards handheld gaming devices. Duration: 01:21 Video provided by AFP
Powered by NewsLook.com
Why Did Nike Fire Most Of Its Nike FuelBand Team?

Why Did Nike Fire Most Of Its Nike FuelBand Team?

Newsy (Apr. 19, 2014) — Nike fired most of its Digital Sport hardware team, the group behind Nike's FuelBand device. Could Apple or an overcrowded market be behind layoffs? Video provided by Newsy
Powered by NewsLook.com
Nearly Two Weeks On, The Internet Copes With Heartbleed

Nearly Two Weeks On, The Internet Copes With Heartbleed

Newsy (Apr. 19, 2014) — The Internet is taking important steps in patching the vulnerabilities Heartbleed highlighted, but those preventive measures carry their own costs. Video provided by Newsy
Powered by NewsLook.com
Facebook To Share Nearby Friends Data With Advertisers

Facebook To Share Nearby Friends Data With Advertisers

Newsy (Apr. 19, 2014) — A Facebook spokesperson has confirmed the company will use GPS data from the new Nearby Friends feature for advertising sometime in the future. 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