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Related papers: Secret key rates for an encoded quantum repeater

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Long-distance entanglement is a very precious resource, but its distribution is very difficult due to the exponential losses of light in optical fibres. A possible solution consists in the use of quantum repeaters, based on entanglement…

Quantum Physics · Physics 2021-05-18 Carlo Liorni , Hermann Kampermann , Dagmar Bruss

We formulate the problem of finding the optimal entanglement swapping scheme in a quantum repeater chain as a Markov decision process and present its solution for different repeater's sizes. Based on this, we are able to demonstrate that…

Quantum Physics · Physics 2022-04-27 Evgeny Shchukin , Peter van Loock

In the framework of cavity QED, we propose a quantum repeater scheme that uses coherent light and chains of atoms coupled to optical cavities. In contrast to conventional repeater schemes, we avoid the usage of two-qubit quantum logical…

Quantum Physics · Physics 2016-09-15 Denis Gonţa , Peter van Loock

Long-distance quantum communication requires quantum repeaters to overcome photon loss in optical fibers. Here we demonstrate a repeater node with two memory atoms in an optical cavity. Both atoms are individually and repeatedly entangled…

Quantum Physics · Physics 2021-06-30 S. Langenfeld , P. Thomas , O. Morin , G. Rempe

Quantum repeaters provide an efficient solution to distribute Bell pairs over arbitrarily long distances. While scalable architectures are demanding regarding the number of qubits that need to be controlled, here we present a quantum…

Quantum Physics · Physics 2017-11-10 M. Zwerger , B. P. Lanyon , T. E. Northup , C. A. Muschik , W. Dür , N. Sangouard

The maximum operational range of continuous variable quantum key distribution protocols has shown to be improved by employing high-efficiency forward error correction codes. Typically, the secret key rate model for such protocols is…

Losses are one of the main bottlenecks for the distribution of entanglement in quantum networks, which can be overcome by the implementation of quantum repeaters. The most basic form of a quantum repeater chain is the swap ASAP repeater…

Quantum Physics · Physics 2025-05-21 Kenneth Goodenough , Tim Coopmans , Don Towsley

We describe a quantum repeater protocol for long-distance quantum communication. In this scheme, entanglement is created between qubits at intermediate stations of the channel by using a weak dispersive light-matter interaction and…

Quantum Physics · Physics 2009-11-11 P. van Loock , T. D. Ladd , K. Sanaka , F. Yamaguchi , Kae Nemoto , W. J. Munro , Y. Yamamoto

Quantum networks, integrating quantum communication, quantum metrology, and distributed quantum computing, could provide secure and efficient information transfer, high-resolution sensing, and an exponential speed-up in information…

Memory dephasing and its impact on the rate of entanglement generation in quantum repeaters is addressed. For systems that rely on probabilistic schemes for entanglement distribution and connection, we estimate the maximum achievable rate…

Quantum Physics · Physics 2009-09-12 M. Razavi , M. Piani , N. Lutkenhaus

We generalize measurement-device-independent quantum key distribution [ H.-K. Lo, M. Curty, and B. Qi, Phys. Rev. Lett. 108, 130503 (2012) ] to the scenario where the Bell-state measurement station contains also heralded quantum memories.…

Quantum Physics · Physics 2015-06-16 Silvestre Abruzzo , Hermann Kampermann , Dagmar Bruß

Quantum repeaters enable the generation of reliable entanglement across long distances despite the underlying channel noise. Nevertheless, realizing quantum repeaters poses a difficult engineering challenge due to various device constraints…

Quantum Physics · Physics 2025-12-29 Shin Sun , Daniel Bhatti , Shaobo Gao , David Elkouss , Hiroki Takahashi

The quantum repeater protocol is a promising approach to implement long-distance quantum communication and large-scale quantum networks. A key idea of the quantum repeater protocol is to use long-lived quantum memories to achieve efficient…

Quantum Physics · Physics 2022-01-31 Yunfei Pu , Sheng Zhang , Yukai Wu , Nan Jiang , Wei Chang , Chang Li , Luming Duan

Quantum repeaters promise to deliver long-distance entanglement overcoming noise and loss in realistic quantum channels. A promising class of repeaters, based on atomic ensemble quantum memories and linear optics, follow the proposal by…

Quantum Physics · Physics 2010-04-05 Jonatan Bohr Brask , Anders Sondberg Sorensen

Quantum communication enables a host of applications that cannot be achieved by classical communication means, with provably secure communication as one of the prime examples. The distance that quantum communication schemes can cover via…

Quantum Physics · Physics 2020-05-12 Sebastiaan Brand , Tim Coopmans , David Elkouss

Quantum repeater networks that allow long-distance entanglement distribution will be the backbone of distributed quantum information processing. In this paper we explore entanglement distribution using quantum repeaters with optimized…

Quantum repeaters are an essential building block for realizing long-distance quantum communications. However, due to the fragile nature of quantum information, these repeaters suffer from loss and operational errors. Prior works have…

Quantum Physics · Physics 2025-07-18 Prateek Mantri , Kenneth Goodenough , Don Towsley

We develop techniques to analyse the statistics of completion times of non-deterministic elements in quantum entanglement generation, and how they affect the overall performance as measured by the secret key rate. By considering such…

Quantum Physics · Physics 2019-04-10 Scott E. Vinay , Pieter Kok

We present a quantum repeater scheme based on the recently proposed qubit amplifier [N. Gisin, S. Pironio and N. Sangouard, Phys. Rev. Lett. 105, 070501 (2010)]. It relies on a on-demand entangled-photon pair source which uses on-demand…

Quantum Physics · Physics 2015-06-03 Jiří Minář , Hugues de Riedmatten , Nicolas Sangouard

Long-distance quantum communication necessitates the use of quantum repeaters, which typically include highly coherent quantum memories. We provide a theoretical analysis of the secret key rates for a quantum repeater system incorporating…