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arXiv · 2109.10916

Roller-Coaster in a Flatland: Magnetoresistivity in Eu-intercalated Graphite

A. L. Chernyshev·O. A. Starykh
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Abstract

Novel phenomena in magnetically-intercalated graphite has been a subject of much research, pioneered and promoted by M.~S. and G.~Dresselhaus and many others in the 1980s. Among the most enigmatic findings of that era was a dramatic, roller-coaster-like behavior of the magnetoresistivity in EuC$_6$ compound, in which magnetic Eu$^{2+}$ ions form a triangular lattice that is commensurate to graphite honeycomb planes. In this study, we provide a long-awaited {\it microscopic} explanation of this behavior, demonstrating that the resistivity of EuC$_6$ is dominated by spin excitations in Eu-planes and their highly nontrivial evolution with the magnetic field. Together with our theoretical analysis, the present study showcases the power of the synthetic 2D materials as a source of potentially significant insights into the nature of exotic spin excitations.

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A. L. Chernyshev, O. A. Starykh. 2022-02-12. Roller-Coaster in a Flatland: Magnetoresistivity in Eu-intercalated Graphite. https://doi.org/10.1103/physrevx.12.021010

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