Experimental demonstration of scalable quantum blockchain with exponentially superior quantum communication complexity

• URL: http://arxiv.org/abs/2607.12250v1
• Date: Tue, 14 Jul 2026 01:25:28 GMT
• Title: Experimental demonstration of scalable quantum blockchain with exponentially superior quantum communication complexity
• Abstract summary: We experimentally demonstrate a scalable quantum blockchain protocol based on weak coherent states.<n>The protocol employs a circular quantum Byzantine agreement mechanism that preserves information-theoretic security.<n>Compared with previous schemes, the protocol requires less than 4% of the quantum communication resources.
• Score: 22.368056596656675
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Abstract: To secure modern distributed digital infrastructures, quantum blockchains exploit quantum resources to achieve information-theoretic security and surpass the classical one-third fault-tolerance bound. However, existing high-fault-tolerant protocols face a fundamental scalability challenge: the blockchain trilemma imposes either exponential communication complexity or experimentally demanding multipartite entanglement. Here, we experimentally demonstrate a scalable quantum blockchain protocol based on weak coherent states that achieves an exponential reduction in quantum communication complexity. The protocol employs a circular quantum Byzantine agreement mechanism that preserves information-theoretic security while avoiding multipartite entanglement. We implement this protocol on a photonic integrated circuit platform, realizing a six-node network over commercially available telecommunication infrastructure. Compared with previous schemes, the protocol requires less than 4% of the quantum communication resources. Leveraging this advantage, we further demonstrate a quantum-secured token exchange application achieving a throughput of 805.3 transactions per second with zero failures. These results establish a practical pathway toward scalable quantum blockchain.

Related papers

• Scalable and Highly Fault-Tolerant Circular Quantum Byzantine Agreement [3.997711170980834]
  Quantum Byzantine Agreement (QBA) offers inherent advantages in security and fault tolerance over classical protocols.<n>We propose a multiparty circular QBA protocol that adopts a semi-decentralized architecture, leveraging circular message gathering and quantum digital signatures.<n>Our protocol is experimentally feasible, requiring only weak coherent states, and is compatible with existing star-shaped quantum networks.
  arXiv  Detail & Related papers  (2026-02-12T05:21:11Z)
• Simultaneous Classical and Quantum Communications: Recent Progress and Three Challenges [52.931372025288844]
  We explore novel protocols that enable simultaneous classical and quantum communications.<n>We extend quantum communication capabilities beyond traditional optical bands into the terahertz.<n>We identify open problems that must be addressed to facilitate practical implementation.
  arXiv  Detail & Related papers  (2025-12-11T00:27:08Z)
• Guarantees on the structure of experimental quantum networks [105.13377158844727]
  Quantum networks connect and supply a large number of nodes with multi-party quantum resources for secure communication, networked quantum computing and distributed sensing. As these networks grow in size, certification tools will be required to answer questions regarding their properties. We demonstrate a general method to guarantee that certain correlations cannot be generated in a given quantum network.
  arXiv  Detail & Related papers  (2024-03-04T19:00:00Z)
• A Quantum-Classical Collaborative Training Architecture Based on Quantum State Fidelity [50.387179833629254]
  We introduce a collaborative classical-quantum architecture called co-TenQu. Co-TenQu enhances a classical deep neural network by up to 41.72% in a fair setting. It outperforms other quantum-based methods by up to 1.9 times and achieves similar accuracy while utilizing 70.59% fewer qubits.
  arXiv  Detail & Related papers  (2024-02-23T14:09:41Z)
• Secured Quantum Identity Authentication Protocol for Quantum Networks [2.3317857568404032]
  This paper proposes a quantum identity authentication protocol that protects quantum networks from malicious entanglements. Unlike the existing protocols, the proposed quantum authentication protocol does not require periodic refreshments of the shared secret keys.
  arXiv  Detail & Related papers  (2023-12-10T05:36:49Z)
• Breaking universal limitations on quantum conference key agreement without quantum memory [6.300599548850421]
  We report a measurement-device-independent quantum conference key agreement protocol with enhanced transmission efficiency over lossy channel. Our protocol can break key rate bounds on quantum communication over quantum network without quantum memory. Based on our results, we anticipate that our protocol will play an indispensable role in constructing multipartite quantum network.
  arXiv  Detail & Related papers  (2022-12-10T06:37:53Z)
• Conference key agreement in a quantum network [67.410870290301]
  Quantum conference key agreement (QCKA) allows multiple users to establish a secure key from a shared multi-partite entangled state. In a quantum network, this protocol can be efficiently implemented using a single copy of a N-qubit Greenberger-Horne-Zeilinger (GHZ) state to distil a secure N-user conference key bit.
  arXiv  Detail & Related papers  (2022-07-04T18:00:07Z)
• An Evolutionary Pathway for the Quantum Internet Relying on Secure Classical Repeaters [64.48099252278821]
  We conceive quantum networks using secure classical repeaters combined with the quantum secure direct communication principle. In these networks, the ciphertext gleaned from a quantum-resistant algorithm is transmitted using QSDC along the nodes. We have presented the first experimental demonstration of a secure classical repeater based hybrid quantum network.
  arXiv  Detail & Related papers  (2022-02-08T03:24:06Z)
• Delegating Multi-Party Quantum Computations vs. Dishonest Majority in Two Quantum Rounds [0.0]
  Multi-Party Quantum Computation (MPQC) has attracted a lot of attention as a potential killer-app for quantum networks. We present a composable protocol achieving blindness and verifiability even in the case of a single honest client.
  arXiv  Detail & Related papers  (2021-02-25T15:58:09Z)
• Direct Quantum Communications in the Presence of Realistic Noisy Entanglement [69.25543534545538]
  We propose a novel quantum communication scheme relying on realistic noisy pre-shared entanglement. Our performance analysis shows that the proposed scheme offers competitive QBER, yield, and goodput.
  arXiv  Detail & Related papers  (2020-12-22T13:06:12Z)
• Entanglement transfer, accumulation and retrieval via quantum-walk-based qubit-qudit dynamics [50.591267188664666]
  Generation and control of quantum correlations in high-dimensional systems is a major challenge in the present landscape of quantum technologies. We propose a protocol that is able to attain entangled states of $d$-dimensional systems through a quantum-walk-based it transfer & accumulate mechanism. In particular, we illustrate a possible photonic implementation where the information is encoded in the orbital angular momentum and polarization degrees of freedom of single photons.
  arXiv  Detail & Related papers  (2020-10-14T14:33:34Z)
• Designing a Quantum Network Protocol [0.0]
  We present a quantum network protocol designed to enable end-to-end quantum communication. One of the key challenges in near-term quantum technology is decoherence -- the gradual decay of quantum information. We show that the protocol is able to deliver its service even in the face of significant losses due to decoherence.
  arXiv  Detail & Related papers  (2020-10-06T09:41:14Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.