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Thermal number influence on the quantum teleportation of a thermal Gaussian state.

Marina Cuzminschi, Alexei Zubarev, Аурелиан Исар

Published Mar 2, 2023• 0 citations

Abstract

Implementing of high efficiency quantum teleportation protocols is in the key task for development of accessible and secure quantum communication. For a successful quantum teleportation two conditions should be satisfied: fidelity of teleportation greater then 1/2 for pure states and the existence of the entanglement between resource state modes during all teleportation process. Quantum teleportation using Gaussian states is a perspective direction because they can be easily implemented and manipulated using laser radiation. The simplest case for the continuous variable quantum teleportation represent teleportation of a pure state. However the thermal noise cannot be eliminated from the system, and the thermal component should be taken into account. In this work we put in evidence how the increase of average thermal photon number influence the fidelity of teleportation of a Gaussian state. We use Lindblad master equation and covariance matrix formalism to describe the temporal evolution of studied system and to put in evidence dependence of the fidelity of teleportation on the environment conditions and resource state parameters. As well we calculated the entanglement between the resource state modes to check if all conditions for a successful teleportation are satisfied.

DOI: 10.1117/12.2643045

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