Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Magnetic monopoles detected in a real magnet for the first time

07.09.2009
Researchers from the Helmholtz-Zentrum Berlin für Materialien und Energie have, in cooperation with colleagues from Dresden, St. Andrews, La Plata and Oxford, for the first time observed magnetic monopoles and how they emerge in a real material. They publish this result in the journal Science within the Science Express web site on Sept. 3.

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 show 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, i.e. they emerge from special arrangements of dipoles and are completely different from the constituents of the material. However, alongside this fundamental knowledge, Jonathan Morris explains the further meaning of the results: „We are writing about new, fundamental properties of matter. These properties are generally valid for materials with the same topology, that is for magnetic moments on the pyrochlore lattice. For the development of new technologies this can have big implications. Above all it signifies the first time fractionalisation in three dimensions is observed."

Article in Science Express 3-Sep-2009:
Dirac Strings and Magnetic Monopoles in Spin Ice Dy2Ti2O7
D.J.P. Morris, D.A. Tennant, S.A. Grigera, B. Klemke, C. Castelnovo, R. Moessner, C. Czter-nasty, M. Meissner, K.C. Rule, J.-U. Hoffmann, K. Kiefer, S. Gerischer, D. Slobinsky, and R.S. Perry
Further informations:
HZB
Glienicker Str. 100
14109 Berlin
Dr. Jonathan Morris
Tel.: 030-8062-3150
jonathan.morris@helmholtz-berlin.de
Prof. Dr. Alan Tennant
Tel.: 030-8062-2741
tennant@helmholtz-berlin.de
Press office:
Dr. Ina Helms
Tel.: 030 / 8062-2034
ina.helms@helmholtz-berlin.de

Dr. Jonathan Morris | EurekAlert!
Further information:
http://www.helmholtz-berlin.de

More articles from Physics and Astronomy:

nachricht Smallest transistor worldwide switches current with a single atom in solid electrolyte
17.08.2018 | Karlsruher Institut für Technologie (KIT)

nachricht Protecting the power grid: Advanced plasma switch for more efficient transmission
17.08.2018 | DOE/Princeton Plasma Physics Laboratory

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>