Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Direct spectroscopic evidence for phase competition between the
  pseudogap and superconductivity in Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+{\delta}}$   In the high-temperature ($T_{c}$) cuprate superconductors, increasing
evidence suggests that the pseudogap, existing below the pseudogap temperature
$T$*, has a distinct broken electronic symmetry from that of superconductivity.
Particularly, recent scattering experiments on the underdoped cuprates have
suggested that a charge ordering competes with superconductivity. However, no
direct link of this physics and the important low-energy excitations has been
identified. Here we report an antagonistic singularity at $T_{c}$ in the
spectral weight of Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+{\delta}}$ as a compelling
evidence for phase competition, which persists up to a high hole concentration
$p$ ~ 0.22. Comparison with a theoretical calculation confirms that the
singularity is a signature of competition between the order parameters for the
pseudogap and superconductivity. The observation of the spectroscopic
singularity at finite temperatures over a wide doping range provides new
insights into the nature of the competitive interplay between the two
intertwined phases and the complex phase diagram near the pseudogap critical
point.

13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org