Navigation Links
Quantum entanglement only dependent upon area
Date:9/15/2013

Two researchers at UCL Computer Science and the University of Gdansk present a new method for determining the amount of entanglement a quantum phenomenon connecting two remote partners, and crucial for quantum technology - within part of a one-dimensional quantum system.

In their paper, published this week in Nature Physics, Dr Fernando Brando (UCL Computer Science) and Dr Michał Horodecki (Institute for Theoretical Physics and Astrophysics, University of Gdansk) demonstrate when the correlation between particles in a sample reduces exponentially with distance, the entanglement between one region and the rest of the sample only depends on the area of the boundary between them.

Characterising entangled states is essential for technologies such as quantum computation, quantum communication and quantum cryptography. Entanglement is also the difficulty behind making computer simulations of quantum systems. This finding shows that a large class of quantum systems (those with exponential decay of correlations) has only limited entanglement and so can be simulated easily.

The relationship between area and entanglement was suspected by researchers in this field based on the intuitive argument that if the correlation between particles in a system dropped off rapidly with distance, only nearby particles would be entangled with each other. Therefore, particles far away from a boundary would not participate in entanglement and only the boundary area would be relevant.

However, this tempting idea was undermined by the existence of a counterexample. This seemed to show that even when two regions could be separated by a layer wide enough to cut off nearly all correlation between them, observers would not be able to know as much about each region as they would if they were genuinely isolated. This 'data hiding' phenomenon is a key characteristic of entangled states, where a lack of knowledge of one partner affects what can be measured of the other.

This work resolves the apparent difficulty by combining recent findings from quantum information theory, originally developed for analyzing quantum communication protocols, showing that data hiding cannot hold once exponential decaying correlations are found in all different regions of the system.

Dr Brando says: "We're very excited to have produced this method. It proves something that seemed to be intuitively true, but the reason why it is true has turned out to be quite different from the original intuition. The result also helps us identify cases where there is low entanglement. These are often good candidates for simulation using classical computers not capable of modeling the consequences of quantum phenomena."

Dr Horodecki says: "What I especially like about our result, is that, perhaps for the first time in this domain, we used solely information-theoretic techniques without assuming any specific physical properties of the system other than exponential decaying correlations. This makes the result very general."


'/>"/>

Contact: David Weston
d.weston@ucl.ac.uk
44-020-310-83844
University College London
Source:Eurekalert

Related biology technology :

1. Quantum Resonance Calibration Standards for Photometric Accuracy Replacing Old Fashioned Liquid Reference Standards
2. Perfectly doped quantum dots yield colors to dye for
3. Building quantum states with individual silicon atoms
4. Quantum computers counting on carbon nanotubes
5. Laser-like photons signal major step towards quantum Internet
6. Nature: Smallest vibration sensor in the quantum world
7. Major grant to investigate limits of quantum theory
8. NIST mechanical micro-drum used as quantum memory
9. NIST quantum refrigerator offers extreme cooling and convenience
10. UCSB physicists make discovery in the quantum realm
11. Quantum Cures Announces Breakthrough Approach for Researchers Seeking Cures for Orphan and Rare Diseases
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/3/2016)... 3, 2016  Dr. Thomas P. McHugh , ... The Woodlands, Texas , now offers SculpSure, ... treated fat cells in just 25-minutes, leaving a slimmer ... percent of Americans report feeling bothered by excess weight ... procedures are a growing industry. This innovative new approach ...
(Date:5/2/2016)... ... 2016 , ... StarNet Communications Corp, ( http://www.starnet.com/ ) a leading publisher of ... Desktop modules to its flagship X-Win32 PC X server. The new modules enable ... user’s PC over encrypted SSH. , Traditionally, users of PC X servers deploy the ...
(Date:4/29/2016)... 2016 According to a ... "Separation Systems for Commercial Biotechnology Market - Global ... 2015 - 2023", the separation systems for commercial ... in 2014 and is projected to expand at ... to reach US$ 19,227.8 Mn in 2023. ...
(Date:4/28/2016)... India , April 28, 2016 ... JT, Stirling, and Brayton Cryocoolers), Service (Technical Support, Product ... and Geography - Global Forecast to 2022", published by ... USD 2.94 Billion by 2022, at a CAGR of ... 70 market data Tables and 94 Figures spread through ...
Breaking Biology Technology:
(Date:3/14/2016)... March 14, 2016 NXTD ) ("NXT-ID" ... commerce market, announces the airing of a new series of ... week of March 21 st .  The commercials will air ... popular Squawk on the Street show. --> NXTD ... growing mobile commerce market, announces the airing of a new ...
(Date:3/11/2016)... , March 11, 2016 ... market research report "Image Recognition Market by Technology (Pattern ... and Advertising), by Deployment Type (On-Premises and Cloud), by ... 2022", published by MarketsandMarkets, the global market is expected ... USD 29.98 Billion by 2020, at a CAGR of ...
(Date:3/9/2016)... -- This BCC Research report provides an overview of ... (RNA Seq) market for the years 2015, 2016 and ... data analysis, and services. Use this report ... such as RNA-Sequencing tools and reagents, RNA-Sequencing data analysis, ... segment and forecast their market growth, future trends and ...
Breaking Biology News(10 mins):