New state of matter detected in a two-dimensional material

April 4, 2016
The excitation of a spin liquid on a honeycomb lattice with neutrons. Credit: Genevieve Martin, Oak Ridge National Laboratory

An international team of researchers have found evidence of a mysterious new state of matter, first predicted 40 years ago, in a real material. This state, known as a quantum spin liquid, causes electrons - thought to be indivisible building blocks of nature - to break into pieces.

The researchers, including physicists from the University of Cambridge, measured the first signatures of these fractional particles, known as Majorana fermions, in a two-dimensional material with a structure similar to graphene. Their experimental results successfully matched with one of the main theoretical models for a , known as a Kitaev model. The results are reported in the journal Nature Materials.

Quantum spin liquids are mysterious states of matter which are thought to be hiding in certain magnetic materials, but had not been conclusively sighted in nature.

The observation of one of their most intriguing properties—electron splitting, or fractionalisation—in real materials is a breakthrough. The resulting Majorana fermions may be used as building blocks of quantum computers, which would be far faster than conventional computers and would be able to perform calculations that could not be done otherwise.

"This is a new quantum state of matter, which has been predicted but hasn't been seen before," said Dr Johannes Knolle of Cambridge's Cavendish Laboratory, one of the paper's co-authors.

In a typical magnetic material, the electrons each behave like tiny bar magnets. And when a material is cooled to a low enough temperature, the 'magnets' will order themselves, so that all the north magnetic poles point in the same direction, for example.

But in a material containing a spin liquid state, even if that material is cooled to absolute zero, the bar magnets would not align but form an entangled soup caused by quantum fluctuations.

"Until recently, we didn't even know what the experimental fingerprints of a quantum spin liquid would look like," said paper co-author Dr Dmitry Kovrizhin, also from the Theory of Condensed Matter group of the Cavendish Laboratory. "One thing we've done in previous work is to ask, if I were performing experiments on a possible quantum spin liquid, what would I observe?"

Knolle and Kovrizhin's co-authors, led by the Oak Ridge National Laboratory, used neutron scattering techniques to look for experimental evidence of fractionalisation in crystals of ruthenium chloride (RuCl3). The researchers tested the magnetic properties of the RuCl3 crystals by illuminating them with neutrons, and observing the pattern of ripples that the neutrons produced on a screen.

A regular magnet would create distinct sharp spots, but it was a mystery what sort of pattern the Majorana fermions in a quantum would make. The theoretical prediction of distinct signatures by Knolle and his collaborators in 2014 match well with what experimentalists observed on the screen, providing for the first time direct evidence of a liquid and the fractionalisation of electrons in a two dimensional material.

"This is a new addition to a short list of known quantum states of matter," said Knolle.

"It's an important step for our understanding of quantum matter," said Kovrizhin. "It's fun to have another new quantum state that we've never seen before - it presents us with new possibilities to try new things."

Explore further: A key to development of materials for the foundation of quantum computers

More information: Proximate Kitaev quantum spin liquid behaviour in a honeycomb magnet, Nature Materials, DOI: 10.1038/nmat4604

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HannesAlfven
2.1 / 5 (15) Apr 04, 2016
Electron fractionalization is one of the features of the Electric Universe. Wal Thornhill points to the work of Ralph Sansbury, who terms the electron pieces as subtrons.

Advocates for conventional theory should be aware that it is possible to explain gravity with this approach w/o any need for Relativity. In this view, gravity is really quite similar to the Van der Waals force -- a collective alignment of these subtron orbitals.

Either electrons can break into pieces, or they cannot. Why call it a "new state of matter"? All of the theoretical benefits are lost when it is assumed that this phenomenon is not happening at all times.
Captain Stumpy
3.7 / 5 (12) Apr 04, 2016
Advocates for conventional theory should be aware that it is possible to explain gravity with this approach w/o any need for Relativity
@ha
is that why you, thorny wal, sansubbly and the rest of the eu have all those nobel prizes for the published paper on that....

oh wait!
if you have a peer reviewed journal paper to share, you would have linked it

the problem with your statement is that you make a claim ("it is possible to explain gravity with this approach w/o any need for Relativity")

but you fail to provide any evidence of said claim, and the reputable science evidence points to the opposite of your claim

so you posted a *false claim*
http://www.auburn...ion.html

just because you want to believe it doesn't mean it really is true
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ogg_ogg
5 / 5 (3) Apr 04, 2016
This is HUGE news! Those rascally Condensed Matter Physicists have stolen the march on those Luddite Particle Physicists! Split the electron, huh? Wow! If I'm not mistaken, all that's left to do to demonstrate the theoretical possibility of warp drive is to show how a single quark can exist in isolation, and then its "beam me up, Scotty"!!!
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Steelwolf
2.3 / 5 (3) Apr 04, 2016
And folks were so recently telling me that Electrons could not be broken down further! These magnetic majorama; Skrmyions, that show very similar traits to the quantum knots I have posted on as well as their remarkably similar structure to the grander scale of our Galaxy. The quantum knot, as was done with the Rubidium atoms in a BEC under a specific magnetic setup, showed an item at that fractal scale that explains why stars at different points in radius from the center of the galaxy are moving at approximately the same speeds: They are following orbitals of a flattened toroidal form just like the inner loops did with the Rubidium, and the larger clouds of mass at the poles as well as a 'magnetic' outer boundary forming like elliptical galaxies. Skyrmion majoramas from electrons sound a lot akin to this as they seem to have similar, if not identical properties when the fractal scalar is applied with the constant being C, or that of the speed of light, no matter the scale.
HannesAlfven
2.3 / 5 (9) Apr 04, 2016
Re: "but you fail to provide any evidence of said claim, and the reputable science evidence points to the opposite of your claim"

What is the actual reason that you, Captain Stumpy, hold so firmly to the electron as a fundamental particle? Please explain the chain of logic which brought you to this apparent conviction you have.
Captain Stumpy
3 / 5 (10) Apr 04, 2016
Please explain the chain of logic
ha
nice redirect from the topic!

*but*

lets go back to the claim i actually quoted
Advocates for conventional theory should be aware that it is possible to explain gravity with this approach w/o any need for Relativity
"this apparent conviction [i] have" is because you made this particular claim and it has absolutely no credible, reputable, or scientific evidence to support it

but instead, you change the argument!
(imagine that) change the goal post because you know that you have no evidence for the claim you made

so- is that a red herring? strawman? distraction? stupidity? or is that simple avoidance of reality?

what thought tactic are you using to avoid the obvious fallacious comment you posted?
the reptilian fast thinking brain?
or the slow methodical logical one?

feel free to expound on either the evidence for "no need for relativity" or your "brain tactics"

thanks
HannesAlfven
2.1 / 5 (7) Apr 04, 2016
From http://www.holosc...niverse/

"Without accepting his model in its entirety, I consider Ralph Sansbury's straightforward electrical theory of magnetism and gravity[15] to have conceptual merit. Simply stated, all subatomic particles, including the electron, are resonant systems of orbiting smaller electric charges of opposite polarity that sum to the charge on that particle. These smaller electric charges he calls 'subtrons.' This is the kind of simplification of particle physics required by Ockham's razor and philosophically agreeable, though it leaves unanswered the real nature and origin of the subtrons. In this model, the electron cannot be treated like a fundamental, point-like particle. It must have structure to have angular momentum and a preferred magnetic orientation, known vaguely as 'spin.' There must be orbital motion of subtrons within the electron to generate a magnetic dipole."

[...]
HannesAlfven
2.8 / 5 (9) Apr 04, 2016
"The transfer of energy between the subtrons in their orbits within the classical electron radius must be resonant and near instantaneous for the electron to be a stable particle. The same argument applies to the proton, the neutron, and, as we shall see —the neutrino.

This model satisfies Einstein's view that there must be some lower level of structure in matter to cause resonant quantum effects. It is ironic that such a model requires the electric force between the charges to operate incomparably faster than the speed of light in order that the electron remain a coherent particle. It means that Einstein's special theory of relativity, that prohibits signalling faster than light, must be repealed. A recent experiment verifies this.

Electromagnetic waves are far too slow to be the only means of signalling in an immense universe. Gravity requires the near-instantaneous character of the electric force to form stable systems like our solar system and spiral galaxies."

[...]
Captain Stumpy
2.8 / 5 (11) Apr 04, 2016
From http://www.holosc...niverse/
@ha
so, you have no reputable evidence at all then?
might i also add that your link is:
1- to a known pseudoscience site
2- is not a journal or peer reviewed paper
3- is a blog of wally thorns, therefore opinion, not science
4- references a book, because they can't actually say "read this peer reviewed paper with actual evidence and science and sh*t, yo"
5- still does not, in any way, support or justify your comment about "no need for relativity"

this must be your way of saying: i aint got evidence, but if you read this random interwebz link, i am sure you will see that even 4chan supports us as being legit

well, your comment is more 4chan/b/ and less Science

let me share one that refutes all your thorny links
http://ocw.mit.ed...ophysics
HannesAlfven
2.5 / 5 (8) Apr 04, 2016
"What is gravity?

Gravity is due to radially oriented electrostatic dipoles inside the Earth's protons, neutrons and electrons. [18] The force between any two aligned electrostatic dipoles varies inversely as the fourth power of the distance between them and the combined force of similarly aligned electrostatic dipoles over a given surface is squared. The result is that the dipole-dipole force, which varies inversely as the fourth power between co-linear dipoles, becomes the familiar inverse square force of gravity for extended bodies. The gravitational and inertial response of matter can be seen to be due to an identical cause. The puzzling extreme weakness of gravity (one thousand trillion trillion trillion trillion times less than the electrostatic force) is a measure of the minute distortion of subatomic particles in a gravitational field."

It's an elegant idea worthy of research, for if it is right, then it is far more ACTIONABLE than Einstein's metaphysics.
Captain Stumpy
3 / 5 (10) Apr 04, 2016
Einstein's metaphysics
@ha
1- Einstein's theories are some of the most validated theories to date
2- Einstein's theories have been thoroughly peer reveiwed by far more than just the situational peer review of a singular paper and journal

most importantly, and this is something you should remember:
wally t and the gang of usual idiots and the eu are some of the least, i repeat *least* peer reviewed idiots in science to date (with the exception of the creationists... but at least they started their own journal to promote and "review" their own religious clap-trap)

so, lets start again: do you have any evidence that would directly refute GR/SR and prove your eu has at least a snowball's chance in hell of being semi-accurate?

PS - all science is worthy of research, but you're not actually posting science
you're posting conjecture and religious belief (you believe because you can't actually produce evidence of said belief, as noted above)
- other than "'you said so"
HannesAlfven
2.6 / 5 (10) Apr 04, 2016
Captain Stumpy gives us his recipe for eliminating actual thinking in science -- because, God forbid, somebody might have a thought which has not been vetted by an expert defending prior research.

Now, he will spam the comments in order to bury the invitation to think.
Captain Stumpy
2.6 / 5 (10) Apr 04, 2016
Captain Stumpy gives us his recipe for eliminating actual thinking in science
@ha
no... i am giving the recipie for critical thinking and evidence based science

IOW - actual science

unlike you who is promoting the religious guesswork based upon the adherence of claims from a supposed authority who was never educated enough in the subject to actually promote any evidence based science in it

i don't care if you have a belief

what i care about is being able to promote science and actually link evidence for said claims

none of which the idiot eu clan can actually do

so... you claim it is science?
where is the evidence?
source is important, alfvie... even your actual Alfven knew that one
thorny even knows it, that is why he can't produce evidence that will convince actual people trained in the subject
(critical thinking 101 - no evidence equals bullsh*t and faith)

so bring on the actual peer reviewed evidence
and quit posting pseudoscience
HannesAlfven
3.2 / 5 (11) Apr 04, 2016
Re: "i am giving the recipie for critical thinking"

The term "critical thinking" was never meant to exclusively mean defense of textbook theory. You might be the only person who does not get this.
Captain Stumpy
3 / 5 (8) Apr 04, 2016
The term "critical thinking" was never meant to exclusively mean defense of textbook theory. You might be the only person who does not get this.
@ha
i noticed you left out something important
it was this part
and evidence based science
so, what you are doing is chery-picking data to make a point about a faith you have in the argument from authority someone else is making about the science behind how the universe and gravity works even though they don't know the first thing about gravity, science or how the scientific method actually works?

is that about it?

so - what part of the brain and thinking method is that again?

.

tell you what: when thrny et al actually usurp the GR/SR with actual evidence, prediction that works, peer reviewed journal papers and validation of claims, just like everything else in science... then you can come back and say "told you so"

NC17
5 / 5 (4) Apr 04, 2016
In the article they talk about "two-dimensional material", which seems at the very least unintuitive.

I'm probably missing something fundamental here, but how can any physical material be 2-dimensional? Aren't 3 dimensions required for any sort of matter in our physical universe?
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NC17
5 / 5 (3) Apr 04, 2016
It just means that the electrons can move along plane - usually thin layer - only. Graphene is 2-D material, for example. The restriction in motion is important for to get the Dirac electron: such an electron doesn't jump and undulate - http://i.imgur.com/ZGqDNfp.gif in time dimension, i.e. its deBroglie wave repeatedly expands and collapses like the bubble.


Ah, so it basically is just about what motion the electrons can have in the material - not that the material itself is somehow lacking a dimension. That makes perfect sense - thanks!
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Apr 04, 2016
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Da Schneib
3.8 / 5 (4) Apr 04, 2016
This is HUGE news! Those rascally Condensed Matter Physicists have stolen the march on those Luddite Particle Physicists! Split the electron, huh? Wow! If I'm not mistaken, all that's left to do to demonstrate the theoretical possibility of warp drive is to show how a single quark can exist in isolation, and then its "beam me up, Scotty"!!!
You should have a "/sarcasm" indicator so you don't get 1s from the snooks.
compose
Apr 04, 2016
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Da Schneib
5 / 5 (4) Apr 04, 2016
In the article they talk about "two-dimensional material", which seems at the very least unintuitive.

I'm probably missing something fundamental here, but how can any physical material be 2-dimensional? Aren't 3 dimensions required for any sort of matter in our physical universe?
They're using a graphene-like sheet material, and the interactions are all on the surface of the material. That's as close to 2D as you get in the real world.

Good question!
Wonder3
5 / 5 (1) Apr 04, 2016
For what it´s worth...

For the believers in electron = fundamental particle.
Here´s the connection between micro and macro.
phys.org/news/2016-01-fundamental-quantum-mechanical-property
antialias_physorg
4.3 / 5 (6) Apr 05, 2016
I'm probably missing something fundamental here, but how can any physical material be 2-dimensional?

It's one layer. There are only two degrees of freedom. Hence: two dimensional.
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Apr 05, 2016
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hazyj
3.7 / 5 (3) Apr 07, 2016
Many thanks to people like Captain Stumpy who choose to continue the fight against such persistent non-scientific non-sense. I know some would say you're just wasting your time, but I wouldn't. Just the opposite - these people need to be put where they belong which is usually somewhere between 2nd grade math class and the nearest vortex.

It's exhausting as hell, aint it? To answer one of your excellent questions, I typically end up settling on the word "stupid" as a means of explaining the phenomena in its entirety. It refers not only to the lack of experience and tools available, but to what is often the meat of the problem: horrible judgement.
hazyj
not rated yet Apr 07, 2016
antialias - while your answer is correct it's too simplistic IMO. For it to be meaningful one would need to answer the question of HOW one keeps electrons to 2D only. That is my question, and Da Schneib approaches a great answer but still an approximation of course as I'm sure was his intention.

Can someone with adequate condensed matter chops explain how an *approximately* 2D structure like the surface of graphene can actually act like 2D? My first question would be this: won't electrons on this surface still move in a transverse direction often enough to muddy the results of experiments?
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