Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unusual normal and superconducting state properties observed in
  hydrothermal Fe1-xSe flakes   The electronic and superconducting properties of Fe1-xSe single-crystal
flakes grown hydrothermally are studied by the transport measurements under
zero and high magnetic fields up to 38.5 T. The results contrast sharply with
those previously reported for nematically ordered FeSe by
chemical-vapor-transport (CVT) growth. No signature of the electronic
nematicity, but an evident metal-to-nonmetal crossover with increasing
temperature, is detected in the normal state of the present hydrothermal
samples. Interestingly, a higher superconducting critical temperature Tc of
13.2 K is observed compared to a suppressed Tc of 9 K in the presence of the
nematicity in the CVT FeSe. Moreover, the upper critical field in the
zero-temperature limit is found to be isotropic with respect to the field
direction and to reach a higher value of ~42 T, which breaks the Pauli limit by
a factor of 1.8.

35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an