Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scrambling in the Dicke model   The scrambling rate $\lambda_L$ associated with the exponential growth of
out-of-time-ordered correlators can be used to characterize quantum chaos. Here
we use the Majorana Fermion representation of spin $1/2$ systems to study
quantum chaos in the Dicke model. We take the system to be in thermal
equilibrium and compute $\lambda_L$ throughout the phase diagram to leading
order in $1/N$. We find that the chaotic behavior is strongest close to the
critical point. At high temperatures $\lambda_L$ is nonzero over an extended
region that includes both the normal and super-radiant phases. At low
temperatures $\lambda_L$ is nonzero in (a) close vicinity of the critical point
and (b) a region within the super-radiant phase. In the process we also derive
a new effective theory for the super-radiant phase at finite temperatures. Our
formalism does not rely on the assumption of total spin conservation.

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The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph