Quantum Blockchain Survey: Foundations, Trends, and Gaps

TL;DR

This survey reviews the foundational concepts, recent developments, and open challenges in quantum blockchain technology, focusing on quantum-resistant cryptography and quantum-enabled blockchain architectures to ensure security in the quantum era.

Contribution

It provides a comprehensive comparison of quantum blockchain approaches, analyzing cryptographic foundations, design trade-offs, and identifying key open research problems.

Findings

Quantum computing threatens classical blockchain security.

Post-quantum and quantum blockchain approaches are evolving.

Open challenges remain in hardware, consensus, and scalability.

Abstract

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.