Mei-Sheng Zhao

Quantum key distribution (QKD) provides a way to share unconditional secure key between two remote parties, but the deviation between theory and practice will break the security of generated key. In this article, we evaluate the security of QKD with weak basis-choice flaw, in which the random bit used by Alice and Bob to determine their bases are weakly controlled by Eve. In fact, a tight and analytical bound is obtained to estimate the phase error for both single photon source and weak coherent source, then the key rate can be rapidly improved. And the key rate of QKD with biased bases is also considered, in which Alice and Bob distill key from two bases independently. Furthermore, by evaluating the security of QKD under wavelength attack, the performance of a commercial beam splitter is measured, and then the key rate is estimated, which is just slightly reduced with our method.