Quantum computing poses fundamental risks to classical blockchain systems by undermining widely used cryptographic primitives. In response, two major research directions have emerged: post-quantum blockchains, which integrate quantum-resistant algorithms, and quantum blockchains, which leverage quantum properties such as entanglement and quantum key distribution. This survey reviews key developments in both areas, analyzing their cryptographic foundations, architectural designs, and implementation challenges. This work provides a comparative overview of technical proposals, highlight trade-offs in security, scalability, and deployment, and identify open research problems across hardware, consensus, and network design. The goal is to offer a structured and comprehensive reference for advancing secure blockchain systems in the quantum era.

翻译：量子计算通过破坏广泛使用的密码学原语，对经典区块链系统构成了根本性风险。对此，已出现两大研究方向：后量子区块链，其整合了抗量子算法；以及量子区块链，其利用了诸如纠缠和量子密钥分发等量子特性。本综述回顾了这两个领域的关键进展，分析了其密码学基础、架构设计和实施挑战。本工作对技术提案进行了比较性概述，强调了在安全性、可扩展性和部署方面的权衡，并指出了在硬件、共识机制和网络设计方面尚待解决的研究问题。其目标是为推进量子时代的安全区块链系统提供一个结构化且全面的参考。