Featured Research

from universities, journals, and other organizations

Experimentally testing nonlocality in many-body systems

Date:
June 20, 2014
Source:
ICFO-The Institute of Photonic Sciences
Summary:
Researchers constructed multipartite Bell inequalities built from the easiest-to-measure quantities, the two-body correlators, which are capable of revealing nonlocality in many-body systems. As these are considered a fundamental resource for quantum information theory, this study will pave a new path towards experimental detection of nonlocality in large composite quantum systems.

This image depicts an artistic impression of the experiment.
Credit: ICFO

Science has recently published a study carried out by researchers at ICFO in collaboration with the Institute for Nuclear Research, Hungarian Academy of Sciences, which demonstrates the capability of detecting non-locality in many-body quantum systems by constructing multipartite Bell inequalities involving only two-body correlations.

In Quantum Theory, interactions among particles create fascinating correlations that cannot be explained by any means known to the Classical World. These correlations, usually known to be nonlocal, prove that the Quantum and Classical Worlds differ at the level of elementary particles. They have also become a powerful resource over the years for such real-world applications as the generation of cryptographic keys, which are perfectly secure against any malicious adversary, or perfect random number generators, which are crucial for cryptography, the numerical simulations of complex systems or fair gambling. Last but not least, these nonlocal correlations, aside from entanglement, are expected to shed a completely new light on our understanding of the physics of many-body quantum states.

An important goal for researchers in this field has been to confirm that such nonlocal correlations really exist in Nature. To date, experiments have focussed on the observation of nonlocality in only small quantum systems consisting of few particles, leaving more complex quantum systems completely unstudied. This is simply because the known tools that may reveal nonlocality, the so-called Bell inequalities, involve correlations among many parties that are still out of reach of the current experimental technology dealing with many-body quantum systems.

In this study, the research team at ICFO, comprised by Jordi Tura, Remigiusz Augusiak, Belen Sainz and ICREA Professors at ICFO Antonio Acín and Maciej Lewenstein, in collaboration with T. Vértesi from Hungary, designed classes of multipartite Bell inequalities constructed from the easiest-to-measure quantities, the two-body correlators. They showed that these inequalities are capable of revealing the nonlocality properties of several interesting many-body quantum states, in particular those relevant for nuclear and atomic physics.

They were even able to show that the inequalities proposed by this study could be verified experimentally by measuring the total spin components of the particles, thus opening a wide range of new possibilities for experimental detection of many-body nonlocality in physical systems in which individual particles cannot be addressed. Possible experimental setups in which these inequalities can be studied include cold atomic clouds and the so-called atomic ensembles, ultracold atoms (Bose condensates or spinor Bose condensates) as well as systems of atoms trapped in nanostructures, or systems of trapped ions.

In summary, the authors comment that "Our study has shown that the possibility of experimentally confirming the existence of nonlocal correlations in many-body quantum states is becoming accessible to physicists, something unimaginable before. At the fundamental level, any experiment regarding this matter would certainly provide a new proof that quantum theory correctly describes nature, even when considering complex many-body systems. In practice, a better characterization of these correlations in many-body quantum systems could not only help to create new understanding, it could lead to new applications, for instance in quantum metrology, and in particular in quantum magnetometry.


Story Source:

The above story is based on materials provided by ICFO-The Institute of Photonic Sciences. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. Tura, R. Augusiak, A. B. Sainz, T. Vertesi, M. Lewenstein, A. Acin. Detecting nonlocality in many-body quantum states. Science, 2014; 344 (6189): 1256 DOI: 10.1126/science.1247715

Cite This Page:

ICFO-The Institute of Photonic Sciences. "Experimentally testing nonlocality in many-body systems." ScienceDaily. ScienceDaily, 20 June 2014. <www.sciencedaily.com/releases/2014/06/140620120444.htm>.
ICFO-The Institute of Photonic Sciences. (2014, June 20). Experimentally testing nonlocality in many-body systems. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/2014/06/140620120444.htm
ICFO-The Institute of Photonic Sciences. "Experimentally testing nonlocality in many-body systems." ScienceDaily. www.sciencedaily.com/releases/2014/06/140620120444.htm (accessed August 1, 2014).

Share This




More Matter & Energy News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) — British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
7 Ways to Use Toothpaste: Howdini Hacks

7 Ways to Use Toothpaste: Howdini Hacks

Howdini (July 30, 2014) — Fresh breath and clean teeth are great, but have you ever thought, "my toothpaste could be doing more". Well, it can! Lots of things! Howdini has 7 new uses for this household staple. Video provided by Howdini
Powered by NewsLook.com
Smoked: 2015 Ducati Diavel Vs 2014 Chevy Corvette Stingray Drag Race

Smoked: 2015 Ducati Diavel Vs 2014 Chevy Corvette Stingray Drag Race

Cycle World (July 30, 2014) — The Bonnier Motorcycle Group presents Smoked; a three part video series. In this episode the 2015 Ducati Diavel takes on the 2014 Chevy Corvette Stingray Video provided by Cycle World
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) — A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) 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:
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