Active phase compensation of quantum key distribution system

作者：Chen Wei; Han ZhengFu^*; Mo XiaoFan; Xu FangXing; Wei Guo; Guo GuangCan

来源：Chinese Science Bulletin, 2008, 53(9): 1310-1314.

DOI：10.1007/s11434-008-0023-0

• quantum key distribution
• Faraday-Michelson system
• phase drift
• active phase compensation

Quantum key distribution (QKD) system must be robust enough in practical communication. Besides birefringence of fiber, system performance is notably affected by phase drift. The Faraday-Michelson QKD system can auto-compensate the birefringence of fiber, but phase shift is still a serious problem in its practical operation. In this paper, the major reason of phase drift and its effect on Faraday-Michelson QKD system is analyzed and an effective active phase compensation scheme is proposed. By this means, we demonstrate a quantum key distribution system which can stably run over 37-km fiber in practical working condition with the long-time averaged quantum bit error rate of 1.59% and the standard derivation of 0.46%. This result shows that the active phase compensation scheme is suitable to be used in practical QKD systems based on double asymmetric interferometers without additional devices and thermal controller.

• 出版日期2008-5
• 单位中国科学技术大学