Washington, September 4 (ANI): In a new research, a team of scientists has for the first time observed magnetic monopoles and how they emerge in a real material.
The research was done by scientists from the Helmholtz-Zentrum Berlin fur Materialien und Energie, Germany, in cooperation with colleagues from Dresden, St. Andrews, La Plata and Oxford.
Magnetic monopoles are hypothetical particles proposed by physicists that carry a single magnetic pole, either a magnetic North pole or South pole.
In the material world, this is quite exceptional because magnetic particles are usually observed as dipoles, north and south combined.
However, there are several theories that predict the existence of monopoles.
Among others, in 1931, the physicist Paul Dirac was led by his calculations to the conclusion that magnetic monopoles can exist at the end of tubes - called Dirac strings - that carry magnetic field.
Until now, they have remained undetected.
Jonathan Morris, Alan Tennant and colleagues (HZB) undertook a neutron scattering experiment at the Berlin research reactor. The material under investigation was a single crystal of Dysprosium Titanate.
This material crystallises in a quite remarkable geometry, the so-called pyrochlore-lattice.
With the help of neutron scattering, Morris and Tennant showed that the magnetic moments inside the material had reorganised into so-called "Spin-Spaghetti".
This name comes from the ordering of the dipoles themselves, such that a network of contorted tubes (Strings) develops, through which magnetic flux is transported.
These can be made visible by their interaction with the neutrons which themselves carry a magnetic moment. Thus, the neutrons scatter as a reciprocal representation of the Strings.
During the neutron scattering measurements, a magnetic field was applied to the crystal by the researchers. With this field, they could influence the symmetry and orientation of the strings.
Thereby, it was possible to reduce the density of the string networks and promote the monopole dissociation.
As a result, at temperatures from 0.6 to 2 Kelvin, the strings are visible and have magnetic monopoles at their ends.
The signature of a gas made up by these monopoles has also been observed in heat capacity measured by Bastian Klemke (HZB).
Providing further confirmation of the existence of monopoles and showing that they interact in the same way as electric charges.
In this work, the researchers, for the first time, attest that monopoles exist as emergent states of matter, that is, they emerge from special arrangements of dipoles and are completely different from the constituents of the material. (ANI)