Quantum gas reveals first signs of path-bending monopole

June 29, 2018 by Chris Cesare, Joint Quantum Institute
Credit: Joint Quantum Institute

Magnets, whether in the form of a bar, horseshoe or electromagnet, always have two poles. If you break a magnet in half, you'll end up with two new magnets, each with its own magnetic north and south.

But some theories predict the existence of single-pole magnets—a situation akin to electric charges, which come in either positive or negative chunks. One particular incarnation—called the Yang monopole after its discoverer—was originally predicted in the context of high-energy physics, but it has never been observed.

Now, a team at JQI led by postdoctoral researcher Seiji Sugawa and JQI Fellow Ian Spielman have succeeded in emulating a Yang monopole with an ultracold gas of . The result, which provides another example of using cold quantum gases to simulate other areas of physics, was reported in the June 29 issue of Science.

"This new result links together ideas born in high-energy physics—the Yang monopole—with concepts in condensed matter physics—topological phase transitions—and realizes them in the atomic physics laboratory," Spielman says.

To detect the Yang monopoles in their quantum gas, Spielman, Sugawa and coworkers manipulated the internal compass needles that all carry—a quantum property called spin—using radio waves and microwaves to rotate the needles in specific ways. By cycling the atoms among four different spin orientations, researchers were able to send the atoms on a journey through "spin space" and bring them back to where they started—very much like a traveler on the Earth's surface taking a trip around the globe (but in four dimensions instead of the globe's two).

The team measured the orientation of the atoms' spins after they completed their journey and compared the result to their initial orientations. They found that the atoms' spins didn't return to where they started, a discrepancy that can arise during a trip through curved space . In this case, the size and direction of the deflection matched predictions for the curvature created by a Yang monopole.

To test that the deflections were indeed due to the monopole and not another source, researchers sent the atoms on a different journey, one that attempted to avoid the space-bending singularity created by the monopole. On this new path, the atoms no longer felt an overall tug from the curvature, a strong indication that they had exited the monopole's realm of influence.

Turning the monopole's effects on and off depends only on the big-picture shape of the paths that the atoms take and not on any small wiggles along the way—an indication that the effect is topological. The paths either enclose a or they don't, and this provides a topological feature that could lead to new types of quantum charge pumps, Spielman says.

Explore further: Destruction of a quantum monopole observed

More information: "Second Chern number of a quantum-simulated non-Abelian Yang monopole" Science (2018). science.sciencemag.org/cgi/doi … 1126/science.aam9031

Related Stories

Destruction of a quantum monopole observed

May 17, 2017

Scientists at Amherst College (USA) and Aalto University (Finland) have made the first experimental observations of the dynamics of isolated monopoles in quantum matter.

Monopole current offers way to control magnets

November 13, 2017

In work published in Physical Review Letters, scientists from RIKEN in Japan have discovered interesting new magnetic properties of a type of materials known as "quantum spin ice." These materials demonstrate interesting ...

Physicists discover quantum-mechanical monopoles

April 30, 2015

Researchers at Aalto University (Finland) and Amherst College have observed a point-like monopole in a quantum field itself for the first time. This discovery connects to important characteristics of the elusive monopole ...

Magnetic monopoles in spin ice crystals

November 12, 2015

Today one of the major goals of physicists is to unify the forces of nature into a Grand Unified Theory that could portray a more elegant and comprehensive representation of the Universe. One step towards this big theory ...

New material is a breakthrough in magnetism

April 12, 2010

(PhysOrg.com) -- Researchers from Imperial College London have created a structure that acts like a single pole of a magnet, a feat that has evaded scientists for decades. The researchers say their new Nature Physics study ...

The mysterious missing magnetic monopole

August 9, 2016

You've probably heard of the Higgs boson. This elusive particle was predicted to exist long ago and helped explain why the universe works the way it does, but it took decades for us to detect.

Recommended for you

When electric fields make spins swirl

November 14, 2018

We are reaching the limits of silicon capabilities in terms of data storage density and speed of memory devices. One of the potential next-generation data storage elements is the magnetic skyrmion. A team at the Center for ...

Structure of fossil-fuel source rocks is finally decoded

November 13, 2018

The fossil fuels that provide much of the world's energy orginate in a type of rock known as kerogen, and the potential for recovering these fuels depends crucially on the size and connectedness of the rocks' internal pore ...

Atomic parity violation research reaches new milestone

November 12, 2018

A reflection always reproduces objects as a complete mirror image, rather than just its individual parts or individual parts in a completely different orientation. It's all or nothing, the mirror can't reflect just a little. ...

17 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

ZoeBell
Jun 29, 2018
This comment has been removed by a moderator.
ZoeBell
Jun 29, 2018
This comment has been removed by a moderator.
ZoeBell
Jun 29, 2018
This comment has been removed by a moderator.
Surveillance_Egg_Unit
4 / 5 (4) Jun 30, 2018
After reading THIS:

"But some physics theories predict the existence of single-pole magnets—a situation akin to electric charges, which come in either positive or negative chunks."

I immediately thought of Direct Current electrical systems wrt the Yang monopole, as opposed to Alternating Current. Am I correct?
howhot3
5 / 5 (2) Jun 30, 2018
This is all pretty easy to understand. Just imagine a sphere spinning on it's axis in 3D. One will see a very predictable topology of the EM field connecting the axis of the poles. Now just like in the movie "Flatland", the sphere is actually 4D spinning on a 4D axis, In that case, in the 3D world you might see a monopole or some type of vortex.

In the quantum mechanics of a quantum gas, probabilities could yield something similar I suspect to a 4D spin. It would come in and out of existence as the polar axis appears in the observer's space. The question is what could be used to measure such a transitory 4D effect?
granville583762
3.7 / 5 (6) Jun 30, 2018
Philosopher's gold, many have tried even more have failed
Magnetic fields spin, breaking the spin in half at the femto level is not possible because we get into the infamous half a neutron.
There is a point when subdividing into smaller polar fields where it is the circular properties are the magnetic field is reached and no further subdivision is possible. The reality, there is neither poles or polar it is diametrically apposed spin which gives the impression of polarity because an electron has its dipole moment. And to date no one has split an Electron!
granville583762
3.7 / 5 (6) Jun 30, 2018
A 30 billion light year space-bending singularity
More belief would be forth coming if - "To test that the deflections were indeed due to the monopole and not another source, researchers sent the atoms on a different journey, one that attempted to avoid the space-bending singularity created by the monopole"
The statement "the space-bending singularity created by the monopole" or more precisely space-bending singularity was the killer blow as space is a vacuum a vacuum cannot be bent as it is equally not a singularity because at this precise moment at the very least it is a 30billon light year diameter of trillions of Galaxies.

granville583762
3.5 / 5 (6) Jun 30, 2018
A Monopole is not in isolation, it comes in north and south polarities
As a Bose Einstein condensate is utilising similar temperatures existing in super conductors where both are dealing with magnetic fields and their corresponding electric fields producing electric currents where any rise in the magnetic field cancels the superconductivity.
A theoretical monopole is intrinsically intertwined with magnetic fields, electric fields and electric currents where electric current in the flow of electrons which mostly consist of magnetic fields.
As no one has subdivided an electron, by subdividing it field into a monopole, presumably two poles north and south – I did not notice this point, if a monopole is found it comes in two flavours.
Da Schneib
4 / 5 (8) Jun 30, 2018
Note that there's not an actual monopole in there. What these folks have done is create a *simulation* of a Wu-Yang monopole, by using the spin of atoms in the cold gas and rotating their spins through a full circle in 3D space using radio waves. Although it appears to be a full rotation (360 degrees) in our space, in fact it is not; as a result, the spin that remains after the rotation is not the same as the spin they started with. This is semi-analogous to the rotation of a fermion's phase; a 360 degree rotation of a fermion's phase does not yield the same phase as you started with, but instead yields the opposite phase, although this is only an analogy; in this case there is no "opposite" spin, instead the rubidium atoms show a different spin, not the opposite spin. The space they rotate through is non-Abelian (non-commutative) and therefore yields an unexpected result after a 360 degree rotation.
granville583762
3 / 5 (8) Jun 30, 2018
Belief in a Vacuum and the word of God as a singularity
How many space bending singularities in the vacuum do they distinguish their individual properties graviton, mono poles, the list is long – a vacuum devoid of all material and worldy properties
Presumably this tug is the space-bending singularity the monopole created
phys.org> On this new path, the atoms no longer felt an overall tug from the curvature an indication that they had exited the monopole's realm of influence

The singularity is bending space this implies the magnetic field being the source of the mono poles where the two independent poles are in actuality two singularities where the force of magnetic attraction is the bending of space there by sidelining the actual problem of the electrons magnetic attraction in two opposing singularities creating two opposing space bending properties a difficult concept not too hard to imagine in these infinite spaces are Gravitons with their space bending properties
granville583762
3 / 5 (8) Jun 30, 2018
God in his wisdom also exists in this vacuous vacuum also
When we defer our scientific problems to the singularity and the infinite vacuum of space as duplicitous spaces of the mentioned vacuum being only singular becoming duplicitous in its conjecture as an entity, don't be surprised if the vacuous vacuum becomes an interesting concept that consequently God in his wisdom also exists in this vacuous vacuum also, as the few that come from the Pennines divide in his wisdom postulated it as Norse to dispel this infinite duplicitous soloution to all physics problems as his mission in life to dispel this religious all invading concept he will do science a great favour by expelling this the space-bending singularity, now singularities and if not remedied all of Gods duplicitous disciples will descend.
howhot3
3.8 / 5 (4) Jul 01, 2018
God in his wisdom also exists in this vacuous vacuum...

You make to claims as fact but really are unknown. First, the statement implies god is wise. Without support proof, you could say anything. It doesn't make it true. Is god wise? Second, you also suggest that god exist in a vacuous vacuum.. again without supporting evidence. If he was wise the why would he even want to exist in a vacuum if by definition a vacuum is void of everything.
So by the fact, both statements are false your hole premise is false. You need to question your beliefs even if it hurts to find out, it was all a lie.
granville583762
3.4 / 5 (5) Jul 01, 2018
God in his wisdom also exists in this vacuous vacuum
You make to claims as fact but really are unknown. First, the statement implies god is wise. Without support proof, you could say anything. It doesn't make it true. Is god wise? Second, you also suggest that god exist in a vacuous vacuum again without supporting evidence. If he was wise the why would he even want to exist in a vacuum if by definition a vacuum is void of everything.
So by the fact both statements are false your hole premise is false. You need to question your beliefs even if it hurts to find out, it was all a lie

howhot3:- can you not see what this is, why does everyone take things so literally, anyway answering your question as the vacuum of space is infinite in its bounds where else in the begging there was nothing, a definition of the vacuum of space where else but in the vacuum does he exist, God is a spirit like Nessie neither can be disproved, but as I said you read it too literally
ZoeBell
Jul 01, 2018
This comment has been removed by a moderator.
Surveillance_Egg_Unit
3 / 5 (6) Jul 02, 2018
Who is interested about twaddling of dumb chaps about God bellow article about magnetic monopoles..? The senility of people here is incredible...

says ZoeBell

Now, now ZoeBell, don't get your bowels in an uproar over references to the Creator wrt the vacuum of space - or vacuum of anything. Your human eyes are not capable of seeing someone unless He is made of matter so that your 5 senses are unable to detect Him.
However, there are SOME who do have the 'gift' to see the Creator. Many people of the Bible had this 'gift', but MOST people today no longer have it. But some do, and I am one of them.
And no, it is not a delusion or imagination. He IS real.

Now back to the article.
howhot3
3.7 / 5 (3) Jul 02, 2018
God in his wisdom also exists in this vacuous vacuum

Since your posting your belief here in a forum about magnetic monopoles. Wisdom is a human trait. It's an ideal we project on people we socially respect. In the vacuum of space, is there wisdom? I would say no because without your own presents how can you prove that bit of space is filled with wisdom. There is no such thing as faith in a vacuum. You can wish for it all you want, but the vacuum does not include you, your thoughts or anything you project on it. It contains no wisdom, and no god.

However, over empty space I can communicate with you and tell you this because of electromagnetics, physics, science and logic. There is so much better out there than one-man's claim to know something wise.

From Emerson, Lake and Palmer; Brain Salad Surgery, "See the show!".

granville583762
3.4 / 5 (5) Jul 02, 2018
Deferring Science to the vacuous vacuum is deferring to the Spirit World
Only matter exists in the vacuous vacuum because it is a space of cubic dimensions, a vacuous vacuum cannot be bent, stretched, is not a force, is not stretched monopoles as a vacuous vacuum is zero everything except it is infinite in its dimensions which is why matter exists in this infinite dimensional space
Deferring science to the vacuous vacuum is a cop out for want of a descriptive description.
If science cannot explain the force of a monopole why not defer it to the vacuous vacuum and find the real solution later if not probably ever
Which is why "God in his wisdom also exists in this vacuous vacuum" because God is a spirit like Nessie who also cannot be explained because just like God, Nessie is a belief which is why our Nessie is safe for ever
The question is; why are scientists's deferring unsolvable problems to this spirit world?

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.