Researchers refine method for detecting quantum entanglement

June 17, 2016 by David Glanz, RMIT University
Credit: CC0 Public Domain

RMIT quantum computing researchers have developed and demonstrated a method capable of efficiently detecting high-dimensional entanglement.

Entanglement in is the ability of two or more particles to be related to each other in ways which are beyond what is possible in classical physics.

Having information on a particle in an entangled ensemble reveals an "unnatural" amount of information on the other particles.

The researchers' paper, "High-dimensional certification", is being published on Friday 17 June in Scientific Reports.

Dr Alberto Peruzzo, a senior research fellow with RMIT University's School of Engineering and Director of RMIT's Quantum Photonics Laboratory, said: "The method we developed employs only two local measurements of complementary properties. This procedure can also certify whether the system is maximally entangled."

Full-scale relies heavily on entanglement between the individual particles used to store information, the bits, or qubits.

Quantum computing promises to exponentially speed up certain tasks because entanglement allows a vastly increased amount of information to be stored and processed with the same number of qubits.

Peruzzo said: "Together with this increase also comes the problem of needing to measure the device many times to find out what it is truly doing - that is, before the quantum computer is up and running, we need to gather an exponentially large amount of information on how it is performing."

Zixin Huang, a PhD student working on the experiment, said: "The current form of computer encodes information in binary form. A higher dimensional state, however, is a particle that contains a message that can be 0, 1, 2 or more, so much more can be stored and transmitted.

"To date, tools for characterising high-dimensional entangled states are limited. In the future when quantum computers become available, our method can potentially serve as a tool in certifying whether the system has enough entanglement between the qubits.

"It significantly cuts down on the number of measurements needed - in fact, it needs the least number of measurements per dimension. Additionally, unlike some others, this method works for systems of any dimension."

Explore further: Russian scientists make teleportation a 'two-way road' using the same quantum resource

More information: Scientific Reports, DOI: 10.1038/srep27637 , Preprint: https://arxiv.org/abs/1604.05824

Related Stories

Worldwide quantum web may be possible with help from graphs

June 8, 2016

(Phys.org)—One of the most ambitious endeavors in quantum physics right now is to build a large-scale quantum network that could one day span the entire globe. In a new study, physicists have shown that describing quantum ...

Three 'twisted' photons in 3 dimensions

February 29, 2016

Researchers at the Institute of Quantum Optics and Quantum Information, the University of Vienna, and the Universitat Autonoma de Barcelona have achieved a new milestone in quantum physics: they were able to entangle three ...

Recommended for you

Researchers investigate 'why clothes don't fall apart'

April 23, 2018

Cotton thread is made of many tiny fibers, each just 2-3 cm long, yet when spun together the fibers are capable of transmitting tension over indefinitely long distances. From a physics perspective, how threads and yarns transmit ...

Swirling liquids work similarly to bitcoin

April 23, 2018

Fluid dynamics is not something that typically comes to mind when thinking about bitcoin. But for one Stanford physicist, the connection is as simple as stirring your coffee.

Muons spin tales of undiscovered particles

April 20, 2018

Scientists at U.S. Department of Energy (DOE) national laboratories are collaborating to test a magnetic property of the muon. Their experiment could point to the existence of physics beyond our current understanding, including ...

3 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Spaced out Engineer
not rated yet Jun 17, 2016
-An entangled state is a complete description of the combined system.

-In a maximally entangled state nothing is known about the individual subsystems.
arom
Jun 18, 2016
This comment has been removed by a moderator.
Steelwolf
not rated yet Jul 12, 2016
And Entangled States have the same characteristics as Chaotic systems do, having found connection between the two, in another article:
http://phys.org/n...tml#nRlv

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.