Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Type I superconductivity in the Dirac semimetal PdTe2   The superconductor PdTe$_2$ was recently classified as a Type II Dirac
semimetal, and advocated to be an improved platform for topological
superconductivity. Here we report magnetic and transport measurements conducted
to determine the nature of the superconducting phase. Surprisingly, we find
that PdTe$_2$ is a Type I superconductor with $T_c = 1.64$ K and a critical
field $\mu_0 H_c (0) = 13.6$ mT. Our crystals also exhibit the intermediate
state as demonstrated by the differential paramagnetic effect. For $H > H_c$ we
observe superconductivity of the surface sheath. This calls for a close
examination of superconductivity in PdTe$_2$ in view of the presence of
topological surface states.

6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
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
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess