Artificial magnetic monopoles discovered

May 31, 2013
This illustration shows a grid of magnetic vortex structures. Credit: Copyright TUM.

A team of researchers from Cologne, Munich and Dresden have managed to create artificial magnetic monopoles. To do this, the scientists merged tiny magnetic whirls, so-called skyrmions. At the point of merging, the physicists were able to create a monopole, which has similar characteristics to a fundamental particle postulated by Paul Dirac in 1931. In addition to fundamental research, the monopoles may also have application potential. The question of whether magnetic whirls can be used in the production of computer components one day is currently being researched by a number of groups worldwide.

When a magnet is divided, a new magnet with north and south poles is always created. However, a monopole, i.e. a north pole without a or a south pole without a has not yet been discovered. In the current edition of the journal Science, researchers from Cologne, Munich and Dresden describe the discovery of new type of artificial monopole in a solid, i.e. particles, which have similar characteristics to monopoles, but which only exist within materials.

Over the last few years, materials in which magnetic whirls, so-called skyrmions, are formed, have been examined intensively. These whirls influence the movements of the in exactly the same manner as magnetic fields. For this reason, artificial magnet fields are used to describe these whirls as well as their influence on the electrons.

Even if these are not "real" magnetic fields, it is possible to measure them experimentally in the same manner as normal magnet fields as they deflect electrons.

The researchers asked questions as to the consequences of attempting to destroy the magnetic whirls. To do this, the group working under the direction of Prof. Eng from the Technischen Universität Dresden observed magnetic whirls with a magnetic force microscope: a tiny magnetic tip samples the surface of the magnets and measures the direction of the magnetization thus making the ca. 50 nanometer sized whirl visible. They were able to observe on the surface that the magnetic whirls apparently coalesce when the skyrmion phase is destroyed.

What happens, however, within the materials? Measurements taken by the group working under the direction of Prof. Pfleiderer in Munich using neutron scattering suggest that similar processes occur there, but individual whirls were not observed in this manner. For this reason, Stefan Buhrandt and Christoph Schütte working in Prof. Rosch's group at the University of Cologne conducted computer simulations. These showed that the whirls neighbouring the merging process observed on the surface in the experiment also occur within the materials.

This illustration depicts the merging of two magnetic vortices, so-called skyrmions, in the magnetic structure of a material. The point at which the vortices merge displays the properties of an emergent magnetic monopole. When the monopole moves along the direction of the vortices, a skyrmion is created or destroyed. Credit: Image by C. Schuette, copyright University of Cologne

The image schematically shows how two magnetic whirls merge into one.

Due to the fact that every whirl carries an artificial , their creation or destruction occurs at the point of merging. "This means that an artificial has to sit on this point," describes Prof. Rosch, "whenever two magnetic whirls merge in the experiment, an artificial magnetic monopole has flown through surface."

Magnetic monopoles have been searched for in vain in the area of particle physics for a long time. In 1931, postulated the existence of a to explain why electrons and protons carry electrical charges of the same size. This is surprising because the elements of the protons and electrons are completely different fundamental particles. Dirac, however, argued that the existence of a single magnetic monopole would be enough to explain that the charges of all fundamental particles have to be quantized, i.e. exactly an integer multiple of an elementary charge. The newly discovered artificial monopoles fulfil exactly this quantization requirement. "It is fascinating that something as fundamental as a magnetic monopole can be realized in a piece of material," describes Stefan Buhrandt. Despite this, artificial monopoles cannot solve Dirac's problem: only electrons in solid state, but not protons, feel the artificial magnet fields.

In addition to their use for fundamental research, artificial monopoles could also have application potential. Many groups worldwide are currently researching the question of whether magnetic whirls could be used in the production of . If this were possible, one would also have to create and destroy whirls: would then play an important role in this.

Explore further: What is Nothing?

More information: "Unwinding of a Skyrmion Lattice by Magnetic Monopoles" Science, 2013

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ValeriaT
3 / 5 (4) May 31, 2013
It's many times recycled stuff - the contextual character of PhysOrg just makes it even more evident (1, 2, 3, 4, ...)
ValeriaT
3 / 5 (2) May 31, 2013
vacuum-mechanics
1.3 / 5 (13) May 31, 2013
Magnetic monopoles have been searched for in vain in the area of particle physics for a long time. In 1931, Paul Dirac postulated the existence of a fundamental particle to explain why electrons and protons carry electrical charges of the same size. This is surprising because the elements of the protons and electrons are completely different fundamental particles…... "It is fascinating that something as fundamental as a magnetic monopole can be realized in a piece of material," describes Stefan Buhrandt. Despite this, artificial monopoles cannot solve Dirac's problem: only electrons in solid state, but not protons, feel the artificial magnet fields.

By the way instead of finding Magnetic monopoles for explain why electrons and protons carry electrical charges of the same size. Maybe it is easier to understand what the protons and electrons are, how they were created as follow…
http://www.vacuum...21〈=en
Q-Star
2.4 / 5 (7) May 31, 2013
the discovery of new type of artificial monopole in a solid, i.e. particles, which have similar characteristics to monopoles,


Which is it? An artificial monopole? Or something similar to a monopole?

but which only exist within materials.


Then it can't be a monopole, they need to call it something else.
Q-Star
2.5 / 5 (8) May 31, 2013
By the way instead of finding Magnetic monopoles for explain why electrons and protons carry electrical charges of the same size. Maybe it is easier to understand what the protons and electrons are, how they were created as follow…
Link to gobbledegook goes here,,,


Maybe it would be easier to understand what the protons and electrons are,,, with some time spent working at learning something rather than getting frustrated at how much effort is required to learn something.

Just because ya don't understand something, and don't have the perseverance required to learn, would ya expect to trick anyone into to thinking ya actually knew something with all that made up gobbledegook?
antialias_physorg
3.5 / 5 (6) May 31, 2013

Which is it? An artificial monopole? Or something similar to a monopole?


In this case it's: "Monopole is as monopole does".
ValeriaT
1.6 / 5 (7) May 31, 2013
For me it's interesting, that the magnetic monopoles violate the Maxwell-Heaviside-Lorentz theory, in which magnetic monopoles are prohibited with artificial symmetry rekalibration. The magnetic motors (in which their magnets represent sorta monopoles as well) may therefore violate the radiative time arrow and entropy based on spreading of magnetic domains. These domains exhibit so-called the magnetic viscosity (which is the analogy of negentropic phenomena like the undercooling). It can be caused just with formation of skyrmions inside of magnetic domains, the destruction of which is assisted with vacuum fluctuations (scalar, i.e. longitudinal waves of vacuum). Because the formation of skyrmions inhibits the magnetic saturation of material, their destruction could lead into release of macroscopic usable work, the energy of which is literally sucked from vacuum.
Urgelt
5 / 5 (4) May 31, 2013
Um.

Well, they aren't monopoles. Therefore they are not 'artificial' (adjective) monopoles.

In fact, they aren't even particles (which monopoles would have to be, if they exist). What the researchers produced is just a boundary phenomenon. Might be useful, but the way they are trumpeting their find is pure hyperbole.
LarryD
not rated yet Jun 01, 2013
Why does the diagram of the skymion remind me of string theory?
ValeriaT
1.8 / 5 (5) Jun 01, 2013
Because they're unidimensional topological defects of their environment in similar way, like the strings. The skyrmions were already used for demonstration of geometrical aspects of string theory.
they aren't monopoles. Therefore they are not 'artificial' (adjective) monopoles.
The true monopoles may not exist in vacuum, but in more dense environment you can realize the geometries which you like (for example with metamaterials). BTW In dense aether model the black holes with asymmetric jets are monopoles. The existence of scalar waves in vacuum enables magnetic fields to dissipate/gain their energy in sourceless way, which will lead into monopolist behavior. In dense materials the phonons may serve as such a scalar waves, for example.
LarryD
not rated yet Jun 01, 2013
Thanks,ValeriaT. With reference to QAT which I have just finished briefly reading. Although it has some points I agree with it also has some points that I don't. It has many 'holes', literally, which are accepted by the theory yet is a contradiction to the whole of and any AT. I will post these at appropriate times.
Mercury_02
not rated yet Jun 01, 2013
Um.

Well, they aren't monopoles. Therefore they are not 'artificial' (adjective) monopoles.

In fact, they aren't even particles (which monopoles would have to be, if they exist). What the researchers produced is just a boundary phenomenon. Might be useful, but the way they are trumpeting their find is pure hyperbole.


Right. Very cool and perhaps useful, but not Dirac's monopoles.
antialias_physorg
3.2 / 5 (5) Jun 02, 2013
, but not Dirac's monopoles.

Well, duh. It says right so in the header of the article. Notice the word 'artificial'?
ValeriaT
1.8 / 5 (5) Jun 02, 2013
The word "artificial" doesn't imply "relative" or "virtual" (even "artificial" diamonds can be "real"). But the magnetic monopoles aren't true monopoles. It's the similar trick, like the massive bosons for example, which is an oxymoron with respect to general relativity theory. In context of atom nuclei the mesons are behaving like the bosons, albeit they're massive. But inside of dense nuclear fluid even the massive bosons behave like massless particles. The vortex rings in air are massive bosons too (they cannot stay at rest) - but they cannot propagate anywhere outside the massive Earth atmosphere.

The scope of skyrmion monopoles is therefore limited to their layer and they could not exist outside of it. Just in the scope of this dense layer their magnetic lines of force don't connect each other, but the magnetic lines of force are still connected outside the skyrmion layer just in the way, which the Maxwells theory requires.
ValeriaT
1.8 / 5 (5) Jun 02, 2013
The above applies to the assumption, that the vacuum is fully homogeneous stuff. But the vacuum is full of density fluctuations, so that in dense aether model weak magnetic monopoles may exist even in pure vacuum. The "weak" word here means, not all lines of force are connected at the single moment in 3D space - some of them can be scattered via scalar waves (Brownian density fluctuations of vacuum). The existence of such temporal monopoles is allowed even in original Maxwell's theory before it was simplified (symmetrized) with Heavidise and Lorentz. You can imagine the Maxwell waves like the deforms of elastic jelly, which is incompressible, so that the continuity equation (mass/energy conservation) applies to it in each time and space interval. But in dense aether model the vacuum is formed with foam, which is compressible - in this way portion of deform may be scattered via longitudinal waves.
ValeriaT
2 / 5 (4) Jun 02, 2013
Couldn't the monopoles be prepared simply with enclosing of one end of magnet with superconductor case? Superconductors aren't penetrated with magnetic field and they're full of Dirac fermions - so why they couldn't form a Dirac monopole?
antialias_physorg
3 / 5 (4) Jun 02, 2013
The word "artificial" doesn't imply "relative" or "virtual"

But it states these things quite plainly in the article:
have managed to create artificial magnetic monopoles. To do this, the scientists merged tiny magnetic whirls, so-called skyrmions. At the point of merging, the physicists were able to create a monopole, which has similar characteristics to a fundamental particle postulated by Paul Dirac in 1931

What part of this is so hard to understand? Especially: how could one misconstrue this to mean that they are somehow talking about real monpole particles?

Unless you want to be willfully obtuse, of course.
antonima
1 / 5 (1) Jun 02, 2013
Couldn't the monopoles be prepared simply with enclosing of one http://www.aether...ctor.gif with superconductor case? Superconductors aren't penetrated with magnetic field and they're full of Dirac fermions - so why they couldn't form a Dirac monopole?


Probably not, it would just force the magnetic field back inside the magnet somehow. BUT, what if the magnet was a superconductor too??? (is that even possible?) You may get some crazy-dense magnetic fields that way, just between the magnet and the shell. Pure speculation of course.
ValeriaT
2.3 / 5 (3) Jun 04, 2013
what if the magnet was a superconductor too??? (is that even possible?)
Yes
you may get some crazy-dense magnetic fields that way
Not quite, as the magnetic field kills the superconductivity. For example in LHC the magnetic field is limited to 8 Tesla in this way.
Jarek
not rated yet Jun 13, 2013
Monopole requires nonzero divergence of the field - building macroscopic monopole without microscopic ones is exactly like building electrically charged object from neutrons only ...
The magnetic singularity they have (Fig. 1B of Science article) has indeed -1 topological charge (Conley index), but it is not magnetic charge as net flow is zero.
This configuration: field flows into a sphere through both poles and flows out through equator, can be obtained by just aligning two magnets in repelling (S-N N-S) configuration, so it is rather magnetic quadrupole, not monopole ...