General theory of decoy-state quantum cryptography with source errors

Date: 2008-12-02
Authors Xiang-Bin Wang, Cheng-Zhi Peng, Jun Zhang, Lin Yang, and Jian-Wei Pan
Journal No. Phys. Rev. A 77, 042311 (2008)  
Abstract The existing theory of decoy-state quantum cryptography assumes the exact control of each state from Alice’s source. Such exact control is impossible in practice. We develop the theory of decoy-state method so that it is unconditionally secure even if there are state errors of sources, if the range of a few parameters in the states are known. This theory simplifies the practical implementation of the decoy-state quantum key distribution because the unconditional security can be achieved with a slightly shortened final key, even though the small errors of pulses are not corrected.