We propose a new scheme to strengthen the performance of the discrete-modulated continuous-variable measurement-device-independent quantum key distribution (DM-CV-MDI-QKD) protocol by introducing a quantum scissors (QS) operation to Bob’s side. According to the equivalent one-way scheme of the protocol, we further investigate the success probability of the QS operation, and analyze the security of the DM-CV-MDI-QKD equipped with this operation in the asymptotic case. Simulation results show that the QS operation can indeed effectively improve the performance of the existing protocol, and compared with the scheme without QS operation, our proposed scheme has a higher secret key rate and a longer secure transmission distance.

我们提出了一种新方案，通过向鲍勃一侧介绍量子剪刀（QS）操作来增强离散调制连续变量与测量设备无关的量子密钥分配（DM-CV-MDI-QKD）协议的性能。根据该协议的等效单向方案，我们进一步研究了QS操作的成功概率，并分析了在渐近情况下配备此操作的DM-CV-MDI-QKD的安全性。仿真结果表明，QS操作确实可以有效地提高现有协议的性能，并且与没有QS操作的方案相比，该方案具有更高的秘密密钥率和更长的安全传输距离。