Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatial competition of the ground states in 1111 iron pnictides   Using nuclear quadrupole resonance, the phase diagram of 1111
$R$FeAsO$_{1-x}$F$_x$ ($R$$=$La, Ce, Sm) iron pnictides is constructed as a
function of the local charge distribution in the paramagnetic state, which
features low-doping-like (LD-like) and high-doping-like (HD-like) regions.
Compounds based on magnetic rare earths (Ce, Sm) display a unified behavior,
and comparison with La-based compounds reveals the detrimental role of static
iron $3d$ magnetism on superconductivity, as well as a qualitatively different
evolution of the latter at high doping. It is found that the LD-like regions
fully account for the orthorhombicity of the system, and are thus the origin of
any static iron magnetism. Orthorhombicity and static magnetism are not
hindered by superconductivity but limited by dilution effects, in agreement
with 2D (respectively 3D) nearest-neighbor square lattice site percolation when
the rare earth is nonmagnetic (respectively magnetic). The LD-like regions are
not intrinsically supportive of superconductivity, on the contrary of the
HD-like regions, as evidenced by the well-defined Uemura relation between the
superconducting transition temperature and the superfluid density when
accounting for the proximity effect. This leads us to propose a complete
description of the interplay of ground states in 1111 pnictides, where
nanoscopic regions compete to establish the ground state through suppression of
superconductivity by static magnetism, and extension of superconductivity by
proximity effect.

7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph