Cloud-based semi-quantum money

In the 1970s, Wiesner introduced the concept of quantum money, where quantum states serve as currency, offering physical-level unforgeability through quantum mechanics. Yet, traditional proposals often unrealistically assume personal quantum computing access for each user. To address these issues, we propose a cloud-based semi-quantum money (CSQM) scheme. This approach only requires semi-honest third-party quantum clouds, while the rest of the system, including transactions and banks, remains fully classical. We also estimate the computational power required by the quantum cloud and provide a thorough security analysis. Our approach significantly reduces the quantum resource demands on local users and facilitates seamless integration with current classical systems.