论文标题
在湍流通道上与测量设备无关的量子键分布中的动态衰减方案
Dynamic attenuation scheme in measurement-device-independent quantum key distribution over turbulent channels
论文作者
论文摘要
无关测量设备设备的量子密钥分布（MDI QKD）在实践中提供了出色的安全性，因为它可以消除所有检测器侧通道。但是，在自由空间渠道上进行MDI QKD是具有挑战性的。最大的罪魁祸首之一是两个独立的湍流通道的不匹配的传播，导致Hong-ou-mandel的可见性降低，从而降低了秘密关键率。在这里，我们介绍了动态衰减方案，其中通过将明亮的光脉冲从每个用户传输到测量设备，从而实时监视了两个通道中每个通道的传输。根据测量的通道传输，在测量设备的低损耗通道中引入了适当的衰减。我们的仿真结果表明QKD性能有了显着改善，尤其是在使用短键时。
Measurement-device-independent quantum key distribution (MDI QKD) offers great security in practice because it removes all detector side channels. However, conducting MDI QKD over free-space channels is challenging. One of the largest culprits is the mismatched transmittance of the two independent turbulent channels causing a reduced Hong-Ou-Mandel visibility and thus a lower secret key rate. Here we introduce a dynamic attenuation scheme, where the transmittance of each of the two channels is monitored in real time by transmitting bright light pulses from each users to the measurement device. Based on the measured channel transmittance, a suitable amount of attenuation is introduced to the low-loss channel at the measurement device. Our simulation results show a significant improvement of QKD performance, especially when using short raw keys.
