Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chiral Spin Spirals at the Surface of the van der Waals Ferromagnet
  Fe$_3$GeTe$_2$   Topologically protected magnetic structures provide a robust platform for low
power consumption devices for computation and data storage. Examples of these
structures are skyrmions, chiral domain walls, and spin spirals. Here we use
scanning electron microscopy with polarization analysis to unveil the presence
of chiral counterclockwise N\'eel spin spirals at the surface of a bulk van der
Waals ferromagnet Fe$_3$GeTe$_2$ (FGT), at zero magnetic field. These N\'eel
spin spirals survive up to FGT's Curie temperature $T_\mathrm{C}= 220
\mathrm{~K}$, with little change in the periodicity $p=300 \mathrm{~nm}$ of the
spin spiral throughout the studied temperature range. The formation of a spin
spiral showing counterclockwise rotation strongly suggests the presence of a
positive Dzyaloshinskii-Moriya interaction in FGT, which provides the first
steps towards the understanding of the magnetic structure of FGT. Our results
additionally pave the way for chiral magnetism in van der Waals materials and
their heterostructures.

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The categories of this paper are: physics
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: gr-qc