Improvement on "an efficient protocol for the quantum private comparison of equality with W state"
Wenjie Liu, Chao Liu, Hanwu Chen, Zhihao Liu, Min-Xiao Yuan, Jin-Shen Lu · International Journal of Quantum Information · 2014
A quantum private comparison (QPC) protocol based on W states [W. Liu et al., Opt. Commun.284, 3160 (2011)] has pointed out there is a flaw of information leak [Y. B. Li et al., Eur. Phys. J. D.66, 110 (2012)]. In order to solve the problem, a special kind of W-class state is introduced, and its construction framework of quantum circuits is sketched. Based on this kind of W-class states, an improvement on Liu et al.'s protocol is presented. Analysis shows the improvement can not only hold the characteristics of original protocol, but also avoid the information leak that Li et al. pointed out.