Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The generic phase diagram of spin relaxation in solids and the Loschmidt
  echo   The spin relaxation time in solids is determined by several competing energy
scales and processes and distinct methods are called for to analyze the various
regimes. We present a stochastic model for the spin dynamics in solids which is
equivalent to solving the spin Boltzmann equation and takes the relevant
processes into account on equal footing. The calculations reveal yet unknown
parts of the spin-relaxation phase diagram, where strong spin-dephasing occurs
in addition to spin-relaxation. Spin-relaxation times are obtained for this
regime by introducing the numerical Loschmidt echo. This allows us to construct
a generic approximate formula for the spin-relaxation time, $\tau_{\text{s}}$,
for the entire phase diagram, involving the quasiparticle scattering rate,
$\Gamma$, spin-orbit coupling strength, $\mathcal{L}$, and a magnetic term,
$\Delta_{\text{Z}}$ due to the Zeeman effect. The generic expression reads as
$\hbar/\tau_{\text{s}}\approx \Gamma\cdot \mathcal{L}^2
/(\Gamma^2+\mathcal{L}^2+\Delta_{\text{Z}}^2)$.

23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat