Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fully gapped superconductivity without sign reversal in the topological
  superconductor PbTaSe$_2$   We investigate the superconducting gap function of topological superconductor
PbTaSe$_2$. Temperature, magnetic field, and three-dimensional (3D) field-angle
dependences of the specific heat prove that the superconductivity of PbTaSe$_2$
is fully-gapped, with two isotropic $s$-wave gaps. The pair-breaking effect is
probed by systematically increasing non-magnetic disorders through
H$^+$-irradiations. The superconducting transition temperature, $T_{\rm{c}}$,
is found to be robust against disorders, which suggests that the pairing should
be sign-preserved rather than sign-reversed.

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The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom