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Abstract
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In this paper, we discuss a scheme for protecting entanglement between
two qubits by employing the technique of reservoir engineering through
the utilization of a leaky cavity with parity deformed fields. The qubits
are moving inside the cavity reservoir, interacting with each other via
the dipole-dipole coupling, and asymmetrically coupled to the parity
deformed cavity modes. The parity deformed cavity modes introduce an
intensity-dependent coupling between the qubits and cavity which acts
as a control factor. We obtain the time-dependent as well as steady-state
forms of the system’s density matrix when the total excitation number is one. Then, we discuss in detail the effects of different parameters on the
entanglement protection in both the Markovian and non-Markovian
regimes. It is deduced from the numerical results that the initial
entanglement in the moving two-qubit system can be strongly protected
by suitably choosing the parity deformation parameter. We find a region
of qubit–environment couplings with values slightly deviated from the
vicinity of the symmetric couplings configurations that may lead to
much better protection. This region can be extended to include all the
allowed qubit–environment coupling values by tailoring the parity
deformation parameter. We show that a stronger entanglement
protection can be also obtained by regularly increasing the velocity of
the qubits, although, without the parity deformation, higher velocities
do not necessarily guarantee entanglement protection. These results are
helpful for the practical control of entanglement dynamics in the future.
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