Quantum physicists achieve entanglement record

April 16, 2018, University of Innsbruck
Conceptual picture of the new exotic quantum states that have been generated in Innsbruck. The generation of quantum entanglement in a string of 20 single atoms is shown. Entanglement between neighboring atom pairs (blue), atom triplets (pink), atom quadruplets (red) and quintuplets (yellow) was observed, before the system became too complex to characterize with existing techniques. Credit: IQOQI Innsbruck/Harald Ritsch

Entanglement is of central importance for the new quantum technologies of the 21st century. A German-Austrian research team is now presenting the largest entangled quantum register of individually controllable systems to date, consisting of a total of 20 quantum bits. The physicists in Innsbruck, Vienna and Ulm are pushing experimental and theoretical methods to the limits of what is currently possible.

Some of the new quantum technologies ranging from extremely precise sensors to universal quantum computers require a large number of in order to exploit the advantages of quantum physics. Physicists all over the world are therefore working on implementing entangled systems with more quantum bits. The record is currently held by Rainer Blatt's research group at the Institute of Experimental Physics at the University of Innsbruck. In 2011, the physicists entangled 14 individually addressable quantum bits for the first time and thus realized the largest completely entangled quantum register. Now, a research team led by Ben Lanyon and Rainer Blatt at the Institute of Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences, together with theorists from the University of Ulm and the Institute of Quantum Optics and Quantum Information in Vienna, has achieved controlled multi-particle entanglement in a system of 20 quantum bits. The researchers were able to detect genuine multi-particle entanglement between all neighbouring groups of three, four and five quantum bits.

Genuine multi-particle entanglement

Physically, entangled particles cannot be described as individual particles with defined states, but only as a complete system. It is particularly difficult to understand entanglement when numerous particles are involved. Here, a distinction must be made between the entanglement of individual particles and genuine multi-particle entanglement. This can only be understood as a property of the overall system of all particles concerned, and cannot be explained by a combination of the subsystems being entangled.

At the Institute of Quantum Optics and Quantum Information in Innsbruck, the team of physicists used laser light to entangle 20 calcium atoms in an ion trap experiment and observed the dynamic propagation of multi-particle entanglement in this system. "The particles are first entangled in pairs," describes Lanyon. "With the methods developed by our colleagues in Vienna and Ulm, we can then prove the further spread of the entanglement to all neighbouring particle triplets, most quadruplets and a few quintuplets.

These detection methods were developed by Martin Plenio's research group at the University of Ulm and Marcus Huber's team at IQOQI Vienna. "We have chosen a MacGyver approach," says first author Nicolai Friis. "We had to find a way to detect multi-particle entanglement with a small number of feasible measurement settings."

The researchers took a complementary approach: The group around Huber and Friis used a method that only requires a few measurements and whose results can be easily evaluated. In this way, the entanglement of three particles could be demonstrated in the experiment. The theorists from Ulm used a more complex technique based on numerical methods. "Although this technique is efficient, it also reaches its limits because of the sharp increase in computing effort due to the number of quantum bits," says Oliver Marty from Martin Plenio's research group. "That's why the usefulness of this method also came to an end with the detection of real five-particle entanglement."

A big step towards application

"There are quantum systems such as ultra-cold gases in which entanglement between a large number of particles has been detected," says Nicolai Friis. "However, the Innsbruck experiment is able to address and read out every single quantum bit individually." It is therefore suitable for practical applications such as quantum simulations or processing. Rainer Blatt and his team hope to increase the number of bits in the experiment. "Our medium-term goal is 50 ," he says. "This could help us solve problems that the best supercomputers today still fail to accomplish."

The methods developed for the ion trap experiment in Innsbruck will be used more widely, the physicists in Ulm and Vienna are convinced. "We want to push the boundaries of our methods even further," say Friis and Marty. "By exploiting symmetries and focusing on certain observables, we can further optimize these methods to detect even more extensive multi-particle .

The research was published in Physical Review X.

Explore further: 14 quantum bits: Physicists go beyond the limits of what is currently possible in quantum computation

More information: Nicolai Friis et al, Observation of Entangled States of a Fully Controlled 20-Qubit System, Physical Review X (2018). DOI: 10.1103/PhysRevX.8.021012

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xinhangshen
1.6 / 5 (5) Apr 16, 2018
Please be aware that quantum mechanics is wrong because it does not take the effects of aether as the medium of light existing everywhere in the visible part of the universe, participating in all physical processes and delivering electromagnetic forces into account. The existence of aether is the direct conclusion of the disproof of Einstein's relativity (see https://www.resea...lativity and https://www.resea...niversal ).

Therefore, the wave property in the particle-wave duality is more likely the result of the wave of aether rather than the wave of probability which is not a physical substance and can't vibrate to become waves, but the wave of aether generated by the motion of the particle always accompanies the motion of each particle.
Da Schneib
4 / 5 (4) Apr 16, 2018
Unfortunately, @xin, this isn't theory. It's an experiment. Data trumps theory, always, and this is data. Experiments showed aether is bullshit in the 19th century; it's called the Michelson-Morley experiment. Do try to keep up.
Da Schneib
not rated yet Apr 16, 2018
The article would be considerably more informative if the basis or bases of the entanglement were discussed. Instead we got a hand-wave at "it's really complicated."

Do better, physorg.

On edit: luckily, the paper is not paywalled. Just follow the link at the end of the article above.
xinhangshen
2.3 / 5 (3) Apr 17, 2018
Unfortunately, @xin, this isn't theory. It's an experiment. Data trumps theory, always, and this is data. Experiments showed aether is bullshit in the 19th century; it's called the Michelson-Morley experiment. Do try to keep up.


Don't behave so naive and ignorant please!
Da Schneib
5 / 5 (1) Apr 17, 2018
Don't behave so naive and ignorant please!
I'm not the one ignoring an experiment from the nineteenth century; you are.
xinhangshen
1 / 5 (1) Apr 18, 2018
Don't behave so naive and ignorant please!
I'm not the one ignoring an experiment from the nineteenth century; you are.

It is you who is ignorant about what I have studied such as the well-known M-M experiment.
Da Schneib
5 / 5 (1) Apr 18, 2018
It is you who is ignorant about what I have studied such as the well-known M-M experiment.
Then describe it.
szore88
4 / 5 (4) Apr 19, 2018
I can't believe you people are talking about aether.... SMH.... This site has gone DOWN HILL the last few years...
xinhangshen
1 / 5 (1) Apr 20, 2018
Aether dynamics is governed by something like non-linear partial-differential Navier-Stokes equations, not by Maxwell's equations which have involved many wrong concepts such as electric field. The so-called electric field is just to model the force exerting on a particle, but that force is not a field because it's the force exerted by a fluid aether, just like the force exerting on an airplane, which is never a field. The real waves are the solutions of the non-linear partial-differential equations, and can't be simplified as simple transverse waves.
Da Schneib
5 / 5 (3) Apr 20, 2018
So you're sure the Michelson-Morley experiment is wrong, but you can't explain how an interferometer works.

If you can't explain how something works, you don't understand it. If you don't understand something, you can't possibly have any valid reason for declaring it to be incorrect.

I knew I had you on ignore for some reason. Now I remember what it is.
xinhangshen
1 / 5 (1) Apr 20, 2018
Da Schneib, How can you make such conclusions?

Please be aware that M-M experiment only denies a rigid aether, but what I have found is a fluid aether.
milnik
1 / 5 (1) Apr 23, 2018
@xnhangshen,
for the first time I see someone who correctly understood who is the main cause of all the phenomena which science seeks to explain on the basis of the nebulosity that Einstein and Lorenzo introduced into science, and so contaminated it, to go backwards to grasp the true causes of the phenomenon.
Here's to all of you and to all the scientists of the world who deal with this issue:
If something comes from something, they must have some of their backward features. We are also an example of human beings and all living beings. The offspring with their parents have backward mutual mutual relations and characteristics in interaction.
The whole universe is filled with the substance AETHER, from which matter is formed and a certain kind of matter has a backward relationship with Aether, which we can call a "family bond".
milnik
1 / 5 (1) Apr 23, 2018
That's how gravity and magnetism emerge, which I am constantly repeating, but, unfortunately, science is immersed in the incorrect and false experiment of Morley.
Aether is neither matter nor energy, nor is it thick, nor is it rare, nor is it inhomogeneous, but it is something that can be understood only if the structure of the universe and the way of forming matter are known, and from it with the Aether there arise the emergence of gravity and magnetism. This intertwining of particles and their actions at a distance of the same can be explained only by the familiar way of how and from what magnetism forms. As science does not understand this phenomenon, it seeks to enforce its "laws" and the rules by which it should be accepted and solved the problem in the way they have envisioned in their Fatamorgana.
alexander2468
5 / 5 (2) Apr 23, 2018
Aether like darkmatter does not exist
xinhangshen - Aether dynamics is governed by something like non-linear partial-differential Navier-Stokes equations, not by Maxwell's equations which have involved many wrong concepts such as electric field. The so-called electric field is just to model the force exerting on a particle, but that force is not a field because it's the force exerted by a fluid aether, just like the force exerting on an airplane, which is never a field. The real waves are the solutions of the non-linear partial-differential equations, and can't be simplified as simple transverse waves.

As your a fluid drains engineer xinhangshen, you use Navier-Stokes equations in your building work, their not applicable to aether dynamics because Aether like darkmatter does not exist.
milnik
not rated yet Apr 24, 2018
@alexander2468,
Every reasonable and humane being, having the consciousness given to him, in his existence, must and must understand that there must be some substance from which matter is formed. How can matter be formed from matter (dark). What are the characteristics of this dark matter? Why are you so afraid of Aether when you are made of it? Who gave you all these qualities and opportunities to thwart everything around you and the causes of those formations? Even in our human beings, it would sometimes be the Big Bang we originated from. Are you a supporter of all the far-fetched and illogical theories that you are now using futilely and always hitting "head to the wall" when you want to prove something with these contradictory theories. If you do not understand yourself, how you were created, how can you think and make conclusions about what you have formed.
First, get rid of it and you will be clear about Aether and SEU.
milnik
not rated yet Apr 24, 2018
@mackita,
Let's try to explain how magnetism appears in the universe at all, but to use our Aether substance model. Here I give you the advantage, to explain whether Aether influences the formation and appearance of magnetism. I will give my explanation, but if I need to explain in detail, I expect the Nobel Prize.
milnik
not rated yet Apr 24, 2018
In your explanation, there is no evidence what magnetism is and how it arises. If this is not known, it is useless to make "cocktails" of various "findings," "claims," "proofs" that are only personal "imaging" of the phenomenon of controversy.
You mention various waves, some dense ether, movements, effects, and who knows what else, but can there be waves of any kind, and who does not have magnetism? This is not about waves of matter (water, or various fluids and gases), we are talking about electromagnetic wave currents. You must know: that there is a substance from which matter is formed, and later from the interrelationships between matter and that substance, gravity and magnetism develop, from which all the phenomena in the universe develop. You are burdened with the concept of vacuum, where you think there is nothing there, but if it is, that substance is the substance that forms the substance.
You have not given any clear proof of what magnetism is and how it occurs.
milnik
not rated yet Apr 24, 2018
Mackita. Let me help you, and the whole science: the interaction between Aether and free gluons causes the appearance of magnetism. I said enough though this is my copyright.
milnik
not rated yet Apr 25, 2018
All these discusions about the complexity of photons, distance and the rest are just the incentives to know the causes of the ghosts, but none of this can be logical if science does not know how photons are formed, and this applies to all other parts and particles of matter.

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