A fiber-based differential phase shift quantum key distribution scheme with higher key creation efficiency

作者：Zhang, Huani; Wang, Jindong^*; Liu, Xiaobao; Wei, Zhengjun; Liu, Songhao

来源：Optics Communications, 2009, 282(14): 3037-3039.

DOI：10.1016/j.optcom.2009.03.066

• Delay units
• Differential phase shift key
• Differential phase shifts
• Differential-phase-shift quantum key distributions
• Single-photon pulse
• Single-photon source
• Time interval
• Utilization ratios

In this paper, a differential phase shift key distribution system with a selectable delay unit is proposed, in which higher key creation efficiency can be achieved. A photon from a single-photon source is split into four pulses with the same time interval T through two cascaded Mach-Zehnder interferometers. In Bob's site, a 4T delay loop with an optical switch is employed to reuse the two end pulses discarded in the conventional differential phase shift scheme, and then entire superposition of the all single photon pulses is achieved. The utilization ratio of photons can reach 100% in perfect condition.

• 出版日期2009-7-15
• 单位华南师范大学