Featured Research

from universities, journals, and other organizations

Distant artificial atoms cooperate by sharing light: Future applications in advanced quantum devices

Date:
November 14, 2013
Source:
University of Calgary
Summary:
Scientists have shown for the first time that atoms can work collectively rather than independently of each other to share light. Quantum physicists have long discussed such an effect, but it has not been seen before in an experiment.

This is an illustration of the artificial atoms or "qubits" alongside the one-dimensional "waveguide" or transmission line.
Credit: Illustration by Arjan van Loo

An international team of scientists has shown for the first time that atoms can work collectively rather than independently of each other to share light.

Quantum physicists have long discussed such an effect, but it has not been seen before in an experiment.

The team included scientists from ETH Zürich (a leading university in Switzerland) who performed the experiment and theoretical scientists from the Université de Sherbrooke in Quebec and the University of Calgary.

The researchers showed the sharing of light or "photon-mediated interaction" between artificial atoms confined to a one-dimensional quantum system.

Their paper, "Photon-mediated interactions between distant artificial atoms," is published this week in the journal Science.

Research shows long-held theory was accurate

"It's an unobserved effect that has been discussed for decades, and we see it with excellent agreement between theory and experiment," says co-author Barry Sanders, a researcher in the Department of Physics and Astronomy and iCORE Chair of Quantum Information Science.

The two artificial atoms "showed a coherent exchange interaction, something not seen before for distant quantum systems in an open environment," says lead author Arjan van Loo, a PhD student in the Quantum Device Lab at ETH Zürich.

Realizing fundamental quantum interactions between individual quantum systems in one dimension is crucial to advance quantum-based devices.

"Systems like ours are expected to be useful for routing quantum information along quantum communication lines [one-dimensional waveguides] on devices used for quantum information processing or quantum communication," says co-author Andreas Wallraff, professor of Solid-State Physics at ETH Zürich.

Man-made circuits can be engineered to exhibit unnatural but useful behaviour

This research shows that "man-made electrical circuits can now be engineered in such a way to exhibit behaviour that is not possible in 'natural' quantum systems," says co-author Alexandre Blais, associate professor of physics at Université de Sherbrooke.

Getting artificial atoms to work collectively could lead to control of microwave fields in superconducting circuits with benefits, including ways to protect quantum information against "noise" or damage to the signal, says Sanders, director of the University of Calgary's Institute for Quantum Science and Technology. "I think what we've shown is going to be critical for future applications."

The key to the team's approach was to do the experiment in one dimension rather than in three dimensions where the interaction between atoms is weak and declines significantly with distance.

"In our experiment, we surpassed these limitations by specially engineering the critical properties of our artificial quantum systems," says co-author Arkady Fedorov, a postdoc at ETH Zürich when the experiment was done, and now a group leader at the ARC Centre for Excellence for Engineered Quantum Systems at the University of Queensland in Australia.

One-dimensional environment key to research findings

The researchers confined two artificial atoms to one dimension using a waveguide (similar to confining light in an optical fibre), which greatly increased the possibility of the two systems interacting and enabled the researchers to measure this interaction.

Using superconducting circuits, the team was able to put two artificial atoms alongside the waveguide and then send a microwave field through this one-dimensional waveguide.

At a distance of approximately two centimetres -- much larger than typically expected for quantum systems -- the two atom-like systems formed a type of weakly bound molecule, due to the exchange of photons ('particles' of light).

"We also observed how the superconducting circuits either synchronize to emit radiation much more efficiently displaying superradiance (a very bright source of radiation), or how the circuits trap radiation, turning the two systems dark, as they do not emit photons anymore," Wallraff says.

The Canadian theorists used the "Mammouth" supercomputer that is part of a national high-performance computing platform coordinated by Compute Canada to solve analytical equations. They "also worked a lot with the experimentalists to understand intuitively the physics going on," says co-author Kevin Lalumière, a PhD student in physics at Université de Sherbrooke.

Financial support for the research was provided by the Canadian Institute for Advanced Research, Natural Sciences and Engineering Council of Canada, ETH Zürich and Alberta Innovates Technology Futures.


Story Source:

The above story is based on materials provided by University of Calgary. The original article was written by Mark Lowey. Note: Materials may be edited for content and length.


Journal Reference:

  1. Arjan F. van Loo, Arkady Fedorov, Kevin Lalumière, Barry C. Sanders, Alexandre Blais, and Andreas Wallraff. Photon-Mediated Interactions Between Distant Artificial Atoms. Science, 14 November 2013 DOI: 10.1126/science.1244324

Cite This Page:

University of Calgary. "Distant artificial atoms cooperate by sharing light: Future applications in advanced quantum devices." ScienceDaily. ScienceDaily, 14 November 2013. <www.sciencedaily.com/releases/2013/11/131114142132.htm>.
University of Calgary. (2013, November 14). Distant artificial atoms cooperate by sharing light: Future applications in advanced quantum devices. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2013/11/131114142132.htm
University of Calgary. "Distant artificial atoms cooperate by sharing light: Future applications in advanced quantum devices." ScienceDaily. www.sciencedaily.com/releases/2013/11/131114142132.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) — Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) — When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
Powered by NewsLook.com
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) — 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) — Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
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