Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dispersionless orbital excitations in (Li,Fe)OHFeSe superconductors   The superconducting critical temperature $T_{\mathrm{c}}$ of intercalated
iron-selenide superconductor (Li,Fe)OHFeSe (FeSe11111) can be increased to 42 K
from 8 K of bulk FeSe. It shows remarkably similar electronic properties as the
high-$T_{\mathrm{c}}$ monolayer FeSe and provides a bulk counterpart to
investigate the origin of enhanced superconductivity. Unraveling the nature of
excitations is crucial for understanding the pairing mechanism in
high-$T_{\mathrm{c}}$ iron selenides. Here we use resonant inelastic x-ray
scattering (RIXS) to investigate the excitations in FeSe11111. Our high-quality
data exhibit several Raman-like excitations, which are dispersionless and
isotropic in momentum transfer and robust against varying $T_{\mathrm{c}}$.
Using atomic multiplet calculations, we assign the low-energy $\sim 0.3$ and
0.7 eV Raman peaks as local $e_g-e_g$ and $e_g-t_{2g}$ orbital excitations. The
intensity of these two features decreases with increasing temperature,
suggesting a primary contribution of the orbital fluctuations. Our results
highlight the importance of orbital degree of freedom for high-$T_{\mathrm{c}}$
iron selenides.

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The categories of this paper are: hep-ex
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex