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arXiv · 1905.07604

Entanglement dynamics of an arbitrary number of moving qubits in a common environment

Sare Golkar·Mohammad K Tavassoly·Alireza Nourmandipour
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Abstract

In this paper we provide an analytical investigation of the entanglement dynamics of moving qubits dissipating into a common and (in general) non-Markovian environment for both weak and strong coupling regimes. We first consider the case of two moving qubits in a common environment and then generalize it to an arbitrary number of moving qubits. We show that for an initially entangled state, the environment washes out the initial entanglement after a finite interval of time. We also show that the movement of the qubits can play a constructive role in protecting of the initial entanglement. In this case, we observe a Zeno-like effect due to the velocity of the qubits. On the other hand, by limiting the number of qubits initially in a superposition of single excitation, a stationary entanglement can be achieved between the qubits initially in the excited and ground states. Surprisingly, we illustrate that when the velocity of all qubits are the same, the stationary state of the qubits does not depend on this velocity as well as the environmental properties. This allows us to determine the stationary distribution of the entanglement versus the total number of qubits in the system.

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Sare Golkar, Mohammad K Tavassoly, Alireza Nourmandipour. 2019-05-18. Entanglement dynamics of an arbitrary number of moving qubits in a common environment. https://doi.org/10.1364/josab.379261

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