Enhancing quantum time transfer security: detecting intercept-resend attacks with energy-time entanglement

• Published in: New journal of physics Vol. 26; no. 9; pp. 93012 - 93021
• Main Authors: Quan, Runai, Hong, Huibo, Xiang, Xiao, Cao, Mingtao, Li, Xinghua, Li, Baihong, Dong, Ruifang, Liu, Tao, Zhang, Shougang
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.09.2024
• Subjects: Counterfeiting; Energy; energy-time entanglement; Fiber optics; nonlocal dispersion cancellation; nonlocality; quantum time transfer; Science; Security
• ISSN: 1367-2630; 1367-2630
• DOI: 10.1088/1367-2630/ad7634

Quantum time transfer has emerged as a powerful technique, offering sub-picosecond precision and inherent security through the nonlocal temporal correlation property of energy-time entangled biphoton sources. In this paper, we demonstrate the inherent security advantage of quantum time transfer, and the utilization in detecting potential intercept-resend attacks. By investigating the impact of these attacks on the nonlocality identifier associated with nonlocal dispersion cancellation of energy-time entanglement, we establish a security threshold model for detecting intercept-resend attacks. Experimental verification on a 102 km fiber-optic link confirms that even a malicious delay as small as 25 ps can be identified. This investigation serves as a compelling illustration of secure two-way time transfer, safeguarding against intercept-resend attacks, and showcasing its potential applications in fields reliant on authentic time distribution between remote parties.