Biography
Guan-Jie Fan-Yuan is an Assistant Researcher at the University of Science and Technology of China, where he received his Ph.D. in 2020. His research interests include quantum key distribution and related quantum communication tasks, such as quantum position verification and quantum time synchronization. His work has contributed to the development of practical quantum communication systems, including high-rate quantum key distribution, robust quantum networks, and quantum–classical co-transmission technologies.
Abstract
Determining the position of an entity can enable security-critical functionalities, such as position-based authorization for transactions and secure tracking of a high-value target. Classical means, however, have been proven incapable of providing secure position verification in the untrusted-prover case, meaning that a prover can mislead verifiers about its actual position. In this work, we propose and experimentally realize a secure position-verification protocol that leverages quantum optics and relativity within an information-theoretic framework. Using phase-randomized weak coherent states, two verifiers separated by 2 km securely verify the prover’s position with an accuracy better than 75 meters. These results establish secure position-based authentication as a practical possibility, paving the way for applications in financial transactions, disaster response, and authenticated secure communications.