Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Sign-reversing orbital polarization in the nematic phase of FeSe due to
  the $C_2$ symmetry-breaking in the self-energy   To understand the nematicity in Fe-based superconductors, nontrivial
$k$-dependence of the orbital polarization ($\Delta E_{xz}(k)$, $\Delta
E_{yz}(k)$) in the nematic phase, such as the sign reversal of the orbital
splitting between $\Gamma$- and X,Y-points in FeSe, provides significant
information. To solve this problem, we study the spontaneous symmetry breaking
with respect to the orbital polarization and spin susceptibility
self-consistently. In FeSe, due to the sign-reversing orbital order, the hole-
and electron-pockets are elongated along the $k_y$- and $k_x$-axes
respectively, consistently with experiments. In addition, an electron-pocket
splits into two Dirac cone Fermi pockets with increasing the orbital
polarization. The orbital-order in Fe-based superconductors originates from the
strong positive feedback between the nematic orbital order and spin
susceptibility.

37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th