Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Manipulating and protecting entanglement by means of spin environments   We study the dynamical behavior of two initially entangled qubits, each
locally coupled to an environment embodied by an interacting spin chain. We
consider energy-exchange qubit-environment couplings resulting in a rich and
highly non trivial entanglement dynamics. We obtain exact results for the
time-evolution of the concurrence between the two qubits and find that, by
tuning the interaction parameters, one can freeze the dynamics of entanglement,
therefore inhibiting its relaxation into the spin environments, as well as
activate a sudden-death phenomenon. We also discuss the effects of an
environmental quantum phase transition on the features of the two-qubit
entanglement dynamics.

36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int