Dynamic pattern of Skyrmions observed

The illustration demonstrates skyrmions in one of their Eigen modes (clockwise). Credit: Yotta Kippe/HZB

Theoretical work had predicted that it should be possible to use a high-frequency electric field to excite a group of skyrmions in the sample so that their cores will rotate all together, synchronously like a fish swarm, clockwise or counter-clockwise, or alternatively they can even exhibit a “breathing” motion.

Now a team has succeeded in measuring the dynamics of these skyrmions in detail for the first time using a single-crystal sample of Cu2OSeO3.

“Conventional laboratory methods like ferromagnetic resonance, cannot detect directly deflection of the spins in the skyrmion phase and are therefore not suitable for observing selectively their excitations. Therefore, we had to come up with something new”, explains Prof. Christian Back, from Technical University of Munich.

The team succeeded at BESSY II in combining a spin-resolving method with an external microwave field. „The resonant magnetic scattering technique when combined with magnetic vectorial external fields shows where the spins are located in the lattice and how they are oriented in space, and all these for each elemental spin species that may exist in the specimen”, explains Dr. Florin Radu, at the Helmholtz-Zentrum Berlin (HZB), a physicist who developed and set up the VEKMAG end station in cooperation with partners from the Universität Regensburg, Ruhr University Bochum, and Freie Universität Berlin.

The construction and continuing development of the VEKMAG station are supported by the German Federal Ministry of Education and Research (BMBF) and HZB.

Using electric field induced ferromagnetic resonance excitation and recording the x-ray intensity of a so called Bragg peak, the research group demonstrated experimentally for the first time that all three characteristic oscillation modes occur in Cu2OSeO3 – the team observed magnetic skyrmions turning clockwise, counterclockwise, and expanding and contracting (“breathing” mode).

Those modes can be switched and turned around by changing the frequency of the microwave field: Each dynamic mode is achieved for a certain frequency, which further depends on the external magnetic field as well as on other intrinsic parameters of the sample. “This is a first step towards phase specific characterization of controlled skyrmion's gyrational motion”, Radu says.

Media Contact

Antonia Roetger
antonia.roetger@helmholtz-berlin.de

 @HZBde

http://www.helmholtz-berlin.de 

All latest news from the category: Physics and Astronomy

This area deals with the fundamental laws and building blocks of nature and how they interact, the properties and the behavior of matter, and research into space and time and their structures.

innovations-report provides in-depth reports and articles on subjects such as astrophysics, laser technologies, nuclear, quantum, particle and solid-state physics, nanotechnologies, planetary research and findings (Mars, Venus) and developments related to the Hubble Telescope.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors