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arXiv · 2306.01406

Entanglement and Teleportation in a 1-D Network with Repeaters

Ganesh Mylavarapu·Indranil Chakrabarty·Kaushiki Mukherjee·Minyi Huang·Junde Wu
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Abstract

The most simplest form of quantum network is an one dimensional quantum network with a single player in each node. In remote entanglement distribution each of the players carry out measurement at the intermediate nodes to produce an entangled state between initial and final node which are remotely separated. It is imperative to say that the flow of information as well as the percolation of entanglement in a network between the source and target node is an important area of study. This will help us to understand the limits of the resource states as well as the measurements that are carried out in the process of remote entanglement distribution. In this article we investigate how the concurrence of the final entangled state obtained is connected with the concurrences of the initial entangled states present in a 1-D chain. We extend the works done for the pure entangled states for mixed entangled states like Werner states, Bell diagonal states and for general mixed states. We did not limit ourselves to a situation where the measurements are happening perfectly. We also investigate how these relations change when we consider imperfect swapping. We obtain the limits on the number of swappings as well as the success probability measurements to ensure the final state to be entangled state after swapping. In addition to these we also investigate on how much quantum information can be sent from the initial node to the final node (by computing the teleportation fidelity) when the measurement is perfect and imperfect with the same set of examples. Here also we obtain the limits on the number of swapping and the success probability of measurement to ensure that the final state obtained is capable of transferring the information . These results have tremendous future applications in sending quantum information between two quantum processors in remote entangled distribution.

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Ganesh Mylavarapu, Indranil Chakrabarty, Kaushiki Mukherjee, Minyi Huang, Junde Wu. 2023-06-02. Entanglement and Teleportation in a 1-D Network with Repeaters. https://arxiv.org/abs/2306.01406

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