Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical observation of spin-density-wave fluctuations in Ba122
  iron-based superconductors   In iron-based superconductors, a spin-density-wave (SDW) magnetic order is
suppressed with doping and unconventional superconductivity appears in close
proximity to the SDW instability. The optical response of the SDW order shows
clear gap features: substantial suppression in the low-frequency optical
conductivity, alongside a spectral weight transfer from low to high
frequencies. Here, we study the detailed temperature dependence of the optical
response in three different series of the Ba122 system
[Ba$_{1-x}$K$_{x}$Fe$_{2}$As$_{2}$, Ba(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ and
BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$]. Intriguingly, we found that the
suppression of the low-frequency optical conductivity and spectral weight
transfer appear at a temperature $T^{\ast}$ much higher than the SDW transition
temperature $T_{SDW}$. Since this behavior has the same optical feature and
energy scale as the SDW order, we attribute it to SDW fluctuations.
Furthermore, $T^{\ast}$ is suppressed with doping, closely following the doping
dependence of the nematic fluctuations detected by other techniques. These
results suggest that the magnetic and nematic orders have an intimate
relationship, in favor of the magnetic-fluctuation-driven nematicity scenario
in iron-based superconductors.

13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph