Abstract
Quantum teleportation is essential for many quantum information technologies, including long-distance quantum networks. Using fiber-coupled devices, including state-of-the-art low-noise superconducting nanowire single-photon detectors and off-the-shelf optics, we achieve conditional quantum teleportation of time-bin qubits at the telecommunication wavelength of 1536.5 nm. We measure teleportation fidelities of % that are consistent with an analytical model of our system, which includes realistic imperfections. To demonstrate the compatibility of our setup with deployed quantum networks, we teleport qubits over 22 km of single-mode fiber while transmitting qubits over an additional 22 km of fiber. Our systems, which are compatible with emerging solid-state quantum devices, provide a realistic foundation for a high-fidelity quantum Internet with practical devices.
2 More- Received 28 July 2020
- Accepted 16 October 2020
- Corrected 22 July 2021
DOI:https://doi.org/10.1103/PRXQuantum.1.020317
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Corrections
22 July 2021
Correction: An Award number was missing in the Acknowledgments section and has been inserted.
Popular Summary
A functional quantum Internet, a network in which information stored in qubits is shared over long distances through entanglement, would change the fields of secure communication, data storage, precision sensing, and computing. High-fidelity quantum teleportation is essential for secure long-distance communications and a practical quantum Internet. This work presents—for the first time—sustained, long-distance (44 km of fiber) teleportation of time-bin qubits featuring state-of-the-art fidelity () and narrow-band photons with narrow-band entangled photon pairs. The experimental results are supported by an analytical model that accurately accounts for experimental imperfections.
The measurements are performed on the Caltech and Fermilab Quantum Network test beds (CQNET, FQNET), two teleportation systems that have been designed, built, commissioned, and deployed by Caltech’s multidisciplinary multi-institutional public-private research program on Intelligent Quantum Networks and Technologies (IN-Q-NET). IN-Q-NET was jointly founded in 2017 by Caltech, AT&T, Fermi National Accelerator Laboratory, and the Jet Propulsion Laboratory.
These unique quantum network test beds use state-of-the-art solid-state light detectors in a compact fiber-based setup and feature near-autonomous data acquisition, control, monitoring, synchronization, and analysis. The teleportation systems, which are compatible both with existing telecommunication infrastructure and with emerging quantum processing and storage devices, represent a significant milestone towards a practical quantum Internet. These networks are currently being used to improve the fidelity and rate of entanglement distribution, with an emphasis on complex quantum communication protocols and fundamental science. The networks are accessible to multidisciplinary researchers for research and development purposes and will serve both fundamental quantum information science and the development of advanced quantum technologies.