Campus study reveals unique properties of layered 2D materials, resulting skyrmion

Photo of sign for Berkeley Lab
Kyle Garcia Takata/Staff
Campus researchers discovered a material with magnetic characteristics allowing it to form a skyrmion, a complex magnetic arrangement.

Related Posts

UC Berkeley researchers discovered a two-dimensional material with unique magnetic characteristics that allow for the development of a complex magnetic arrangement called a skyrmion in a study.

Hongrui Zhang, a campus postdoctoral researcher, is studying a two-dimensional material that exhibits such new phenomena, according to a Berkeley Lab press release. The press release added that Zhang, alongside another campus postdoctoral researcher, Xiang Chen, discovered via careful magnetic measurements that these materials are ferromagnetic at room temperature, similar to how a kitchen magnet may work, and cannot be superimposed on its mirror image.

“The focus for us is to understand why did it do this?” said Ramamoorthy Ramesh, co-author of the study and faculty senior scientist in Berkeley Lab’s materials sciences division. “What’s the underlying atomic-scale physics that led to the formation of these exotic spin textures?”

Ramesh, who is also a campus physics and material science professor, explained that several members of the physics and materials science departments conduct the fundamental studies of solid-state systems, formally known as condensed matter physics.

Ramesh also explained that there is ongoing research on campus that focuses on the study of quantum materials.

The paths the electrons take in their orbit can be complicated, leading to interesting new phenomena, according to Ramesh.

“These are materials that are very much like human beings. Human beings have a lot of personalities and emotions,” Ramesh said. “These materials are very interactive.”

These interactions between materials are termed “correlations,” according to Ramesh. He added these correlations may be the result of the electronic structure of the material and how the electrons move in their orbit, termed “spin-orbit interactions.”

These characteristics of the material lead to an “exotic” magnetic structure, known as a skyrmion.

The material in question contains iron, cobalt, germanium and tellurium, Ramesh noted. He added that the ratio of iron to cobalt seems to be the most important factor.

Ramesh also noted if the material is at 40% cobalt, skyrmions are unable to form. However, at 50% cobalt and 50%  iron, skyrmions are able to form, he said.

Some researchers are now questioning why the material and these ratios lead to this phenomenon, according to Ramesh. He added that Zhang in particular is now attempting to grow thin films of the material and see if it can be manipulated with an electric field or current.

“Impacting real technology is still far out there, 20 years maybe, but the thing is for much of basic science, we don’t attach strings to it,” Ramesh said. “We want to discover, we want to understand nature, we want to understand how materials behave.”

Contact Ishwari Nagnur at [email protected].