Thermally superactive artificial kagome spin ice structures obtained with the interfacial Dzyaloshinskii-Moriya interaction

Kevin Hofhuis, Aleš Hrabec, Hanu Arava, Naëmi Leo, Yen Lin Huang, Rajesh V. Chopdekar, Sergii Parchenko, Armin Kleibert, Sabri Koraltan, Claas Abert, Christoph Vogler, Dieter Suess, Peter M. Derlet, Laura J. Heyderman

Artificial kagome spin ice exhibits exotic magnetic correlations driven by a combination of geometric frustration and dipolar interactions that, at low-enough temperature, can result in ordered phases. This order, whether it is the ground state of several kagome rings, or the theoretically predicted long-range order of an extended array, has yet to be experimentally observed. By introducing an interfacial Dzyaloshinskii-Moriya interaction, we are able to reduce the blocking temperature of the individual nanomagnets, allowing a system of 30 kagome nanomagnets to explore its vast manifold of microstates and find its ground state. Furthermore, the extracted magnetic correlations in an extended artificial kagome spin ice are found to exhibit quantitative signatures of long-range charge order, providing evidence of the theoretically predicted continuous phase transition to the charge-ordered state. The significant lowering of the blocking temperature in nanomagnets is important for the exploitation of superparamagnetism in artificial spin systems and devices.

Physics of Functional Materials, Research Platform MMM Mathematics-Magnetism-Materials
External organisation(s)
Eidgenössische Technische Hochschule Zürich, Paul Scherrer Institute, University of California, Berkeley, Lawrence Berkeley National Laboratory
Physical Review B
No. of pages
Publication date
Peer reviewed
Austrian Fields of Science 2012
103017 Magnetism
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, Condensed Matter Physics
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