Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ballistic-to-diffusive transition in spin chains with broken
  integrability   We study the ballistic-to-diffusive transition induced by the weak breaking
of integrability in a boundary-driven XXZ spin-chain. Studying the evolution of
the spin current density $\mathcal J^s$ as a function of the system size $L$,
we show that, accounting for boundary effects, the transition has a non-trivial
universal behavior close to the XX limit. It is controlled by the scattering
length $L^*\propto V^{-2}$, where $V$ is the strength of the integrability
breaking term. In the XXZ model, the interplay of interactions controls the
emergence of a transient "quasi-ballistic" regime at length scales much shorter
than $L^*$. This parametrically large regime is characterized by a strong
renormalization of the current which forbids a universal scaling, unlike the XX
model. Our results are based on Matrix Product Operator numerical simulations
and agree with perturbative analytical calculations.

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The categories of this paper are: funct-an
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The categories of this paper are: atom-ph
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The categories of this paper are: q-fin
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The categories of this paper are: math-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin
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The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: gr-qc
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys