Magnets are not everywhere equally magnetized, but automatically split up into smaller areas, so-called magnetic domains. The walls between the domains are of particular importance: they determine the magnetic properties of the material. A research team of material scientists from Kiel University is working on artificially creating domain walls to be able to modify in a controlled way the behaviour of magnets on a nanometre scale. In the long term, this method could also be used for high-speed and energy-efficient data transfer. The research results were recently published in the renowned journal “Scientific Reports”.
Splitting a magnetic material into small domains has significant energy benefits. But the focus of the research team from Kiel University is on the walls which separate the domains from each other.
In the simulation, magnetic signals spread along the domain walls in a few nanoseconds. The signals behave in a wave-like manner, with the initially high amplitude rapidly becoming smaller.
“The position and the density of these walls determine the characteristics of the entire magnetic layer,” said Jeffrey McCord, Professor of Nanoscale Magnetic Materials, with a focus on magnetic domains. “Being able to specifically set the positions of domain walls, therefore, has a major impact – but it's not all that easy to do,” said the leader of the research team.
In order to precisely position the domains and domain walls, the research team used a special method: the scientists irradiated magnetic multilayer films with ions. Domain wall structures, which are normally arranged randomly, can thereby be “imprinted” in the magnetic material as desired.
“In this way, magnetic characteristics can be specifically modified, and on a reproducible basis as well. We can thus determine the positions of the domain walls ourselves and build our own domain wall gratings out of millions of 50-nanometre-wide walls. This allows us to create magnetic materials which display a completely different behaviour to external magnetic fields,” said a delighted McCord.
“We were surprised at how well spin waves spread in the domain walls and are directed by them,” emphasised McCord. Electron spins are also suitable for processing and encoding information.
In the long term, therefore, the discoveries made by the Kiel scientists could be interesting for data transfer that does not take place via electrons, but via magnons – i.e. magnetic information transfer. “With artificially created domain wall structures, we can direct data streams faster and with less energy,” said McCord. Further areas of application include highly-sensitive magnetic sensors.
J. Trützschler, K. Sentosun, B. Mozooni, R. Mattheis, J. McCord. Magnetic domain wall gratings for magnetization reversal tuning and confined dynamic mode localization, Scientific Reports 6, 30761 (2016) DOI: 10.1038/srep30761
Photos are available to download:
In the simulation, magnetic signals spread along the domain walls (DW) in a few nanoseconds (ns). In ten nanoseconds, a ray of light travels three metres. The signals behave in a wave-like manner, with the initially high amplitude rapidly becoming smaller.
Jeffrey McCord has been working as Professor for Nanoscale Magnetic Materials, focusing on magnetic domains, at Kiel University since 2011.
Photo/Copyright: Denis Schimmelpfennig / Kiel University
Institute for Materials Science
Professor for Nanoscale Magnetic Materials
Tel.: +49 (0)431 880 6123
Details, which are only a millionth of a millimetre in size: This is what the research focus "Kiel Nano, Surface and Interface Science – KiNSIS" at Kiel University has been working on. In the nano-cosmos, different laws prevail than in the macroscopic world - those of quantum physics. Through intensive, interdisciplinary cooperation between materials science, chemistry, physics, biology, electrical engineering, computer science, food technology and various branches of medicine, the research focus aims to understand the systems in this dimension and to implement the findings in an application-oriented manner. Molecular machines, innovative sensors, bionic materials, quantum computers, advanced therapies and much more could be the result. More information at www.kinsis.uni-kiel.de
Press, Communication and Marketing, Dr Boris Pawlowski, Text: Julia Siekmann
Postal address: D-24098 Kiel, Germany,
Telephone: +49 (0)431 880-2104, Fax: +49 (0)431 880-1355
E-mail: email@example.com, Internet: www.uni-kiel.de
Twitter: www.twitter.com/kieluni, Facebook: www.facebook.com/kieluni
Dr. Boris Pawlowski | idw - Informationsdienst Wissenschaft
Research finds new molecular structures in boron-based nanoclusters
13.07.2018 | Brown University
3D-Printing: Support structures to prevent vibrations in post-processing of thin-walled parts
12.07.2018 | Fraunhofer-Institut für Produktionstechnologie IPT
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Transportation and Logistics
16.07.2018 | Agricultural and Forestry Science