Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Roller-Coaster in a Flatland: Magnetoresistivity in Eu-intercalated
  Graphite   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.

16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin