Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Anisotropic magnetic excitations from single-chirality antiferromagnetic
  state in Ca-kapellasite   We present a $^{35}$Cl NMR study for spin $S=1/2$ perfect kagome
antiferromagnet Ca-kapellasite (CaCu$_{3}$(OH)$_{6}$Cl$_{2}\cdot$0.6H$_{2}$O)
with a magnetic transition at $T^{\ast}=7.2$ K. The static magnetic structure
in the ground state has been determined to be a chirality-ordered $Q=0$ state,
which is selected by a finite Dzyaloshinskii-Moriya interaction. The low-energy
magnetic excitations in the ordered state are investigated by the nuclear
spin-lattice relaxation rate measurement. We detect a weakly temperature
dependent contribution in the magnetic fluctuations perpendicular to the kagome
plane in addition to the dispersive spin-wave contribution in the kagome plane.
The low-energy magnetic excitations from the coplanar spin structure are
attributed to the zero mode originating from the flat band in this kagome
antiferromagnet.

11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th