Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pseudogap-like phase in Ca(Fe$_{1-x}$Co$_x$)$_2$As$_2$ revealed by
  $^{75}$As NQR   We report $^{75}$As NQR measurements on single crystalline
Ca(Fe$_{1-x}$Co$_x$)$_2$As$_2$ ($0\leq x \leq 0.09$). The nuclear spin-lattice
relaxation rate $T_1^{-1}$ as a function of temperature $T$ and Co dopant
concentration $x$ reveals a normal-state pseudogap-like phase below a crossover
temperature $T^*$ in the under- and optimally-doped region. The resulting
$x$-$T$ phase diagram shows that, after suppression of the spin-density-wave
order, $T^*$ intersects $T_c$ falling to zero rapidly near the optimal doping
regime. Possible origins of the pseudogap behavior are discussed.

1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: eess
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg