Quantum repeater protocol for deterministic distribution of macroscopic entanglement

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Pyrkov, Alexey N., Lazarev, Ilia D., Byrnes, Tim
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916341870493696
author Pyrkov, Alexey N.
Lazarev, Ilia D.
Byrnes, Tim
author_facet Pyrkov, Alexey N.
Lazarev, Ilia D.
Byrnes, Tim
contents Distributing long-distance entanglement is a fundamental goal that is necessary for a variety of tasks such as quantum communication, distributed quantum computing, and quantum metrology. Currently quantum repeater schemes typically aim to distribute one ebit at a time, the equivalent of one Bell pair's worth of entanglement. Here we present a method to distribute a macroscopic amount of entanglement across long-distances using a number of operations that scales only linearly with the chain length. The scheme involves ensembles of qubits and entangling them with an $S^z S^z$ interaction, which can be realized using atomic gas ensembles coupled by a shared optical mode. Using only local measurements on the intermediate ensembles, this leaves the ensembles at the ends of the chain entangled. We show that there are particular ``magic'' interaction times that allow for distribution of entanglement with perfect fidelity, with no degradation with chain length. The scheme is deterministic, such that with suitable local conditional unitary corrections, the same entangled state can always be prepared with good approximation.
format Preprint
id arxiv_https___arxiv_org_abs_2408_00141
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Quantum repeater protocol for deterministic distribution of macroscopic entanglement
Pyrkov, Alexey N.
Lazarev, Ilia D.
Byrnes, Tim
Quantum Physics
Distributing long-distance entanglement is a fundamental goal that is necessary for a variety of tasks such as quantum communication, distributed quantum computing, and quantum metrology. Currently quantum repeater schemes typically aim to distribute one ebit at a time, the equivalent of one Bell pair's worth of entanglement. Here we present a method to distribute a macroscopic amount of entanglement across long-distances using a number of operations that scales only linearly with the chain length. The scheme involves ensembles of qubits and entangling them with an $S^z S^z$ interaction, which can be realized using atomic gas ensembles coupled by a shared optical mode. Using only local measurements on the intermediate ensembles, this leaves the ensembles at the ends of the chain entangled. We show that there are particular ``magic'' interaction times that allow for distribution of entanglement with perfect fidelity, with no degradation with chain length. The scheme is deterministic, such that with suitable local conditional unitary corrections, the same entangled state can always be prepared with good approximation.
title Quantum repeater protocol for deterministic distribution of macroscopic entanglement
topic Quantum Physics
url https://arxiv.org/abs/2408.00141