Quantum repeater using three-level atomic states in the presence of dissipation: stability of entanglement

TL;DR

This paper investigates the stability of entanglement transfer in a quantum repeater protocol using three-level atomic states, considering dissipation effects like spontaneous emission and photon leakage, and identifies conditions for ideal operation.

Contribution

It introduces a model for entanglement transfer with three-level atoms in dissipative environments and analyzes how dissipation affects entanglement stability and success probability.

Findings

Negativity decreases with increased detuning.

Dissipation causes non-periodic negativity evolution.

Entanglement stability can be achieved by parameter control.

Abstract

In this paper we want to investigate the possibility of transferring entanglement to two three-level separable atomic states over large distance using the quantum repeater protocol. In detail, our model consists of eight three-level atoms where only the pairs (1,2), (3,4), (5,6) and (7,8) are prepared in maximally entangled states. Performing suitable interaction between non-entangled three-level atoms (2,3) and (6,7) in two-mode cavities with photon leakage rates in the presence of spontaneous emission leads to producing entanglement between atoms (1,4) and (5,8), separately. Finally, the entanglement between atoms (1,8) is successfully produced by performing interaction between atoms (4,5) while spontaneous emission is considered in a dissipative cavity. In the continuation, the effects of detuning, dissipation and initial interaction time are considered on negativity and success probability of the processes. The maxima of negativity are decreased by increasing the detuning, in most cases. Also, the time evolution of negativity is non-periodic in the presence of dissipation. Increasing the initial interaction time has a constructive effect on negativity in all considered cases. The oscillations of negativity are destroyed as time goes on and the produced entanglement is stabled. The success probability of entangled state of atoms (1,8) is tunable by controlling the detuning and dissipation. We show that via justifying the involved parameters one can arrive at conditions in which the decoherence effects are fully disappeared; as a result an ideal quantum repeater can be achieved while atomic and field dissipations are taken into account.