Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Manipulation of Dirac band curvature and momentum-dependent g-factor in
  a kagome magnet YMn6Sn6   The Zeeman effect describes the energy change of an atomic quantum state in
magnetic field. The magnitude and the direction of this change depend on the
dimensionless Lande g-factor. In quantum solids, the response of the Bloch
electron states to the magnetic field also exhibits the Zeeman effect with an
effective g-factor that was theoretically predicted to be dependent on the
momentum. While typically negligible in many ordinary solids, the
momentum-dependent variation of the g-factor is theorized to be substantially
enhanced in many topological and magnetic systems. However, the
momentum-dependence of the g-factor is notoriously difficult to extract and it
is yet to be directly experimentally measured. In this work, we report the
experimental discovery of a strongly momentum-dependent g-factor in a kagome
magnet YMn6Sn6. Using spectroscopic-imaging scanning tunneling microscopy, we
map the evolution of a massive Dirac band in the vicinity of the Fermi level as
a function of magnetic field. We find that electronic states at different
lattice momenta exhibit markedly different Zeeman energy shifts, giving rise to
an anomalous g-factor that peaks around the Dirac point. Our work provides the
first momentum-resolved visualization of Dirac band curvature manipulation by
magnetic field, which should in principle be highly relevant to other
topological kagome magnets.

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The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
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The categories of this paper are: gr-qc
19
The categories of this paper are: eess
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The categories of this paper are: math
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The categories of this paper are: cs
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The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys