Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Doping dependence of the anisotropic quasiparticle interference in
  NaFe1-xCoxAs iron-based superconductors   We use scanning tunneling microscopy to investigate the doping dependence of
quasiparticle interference (QPI) in NaFe1-xCoxAs iron-based superconductors.
The goal is to study the relation between nematic fluctuations and Cooper
pairing. In the parent and underdoped compounds, where four-fold rotational
symmetry is broken macroscopically, the QPI patterns reveal strong rotational
anisotropy. At optimal doping, however, the QPI patterns are always four-fold
symmetric. We argue this implies small nematic susceptibility and hence
insignificant nematic fluctuation in optimally doped iron pnictides. Since Tc
is the highest this suggests nematic fluctuation is not a prerequistite for
strong Cooper pairing.

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The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys