It is known that quantum scissors, as non-deterministic amplifiers, can enhance the performance of Gaussian-modulated continuous-variable quantum key distribution (CV-QKD) in noisy and long-distance regimes of operation. Here, we extend this result to a non-Gaussian CV-QKD protocol with discrete modulation. We show that, by using a proper setting, the use of quantum scissors in the receiver of such discrete-modulation CV-QKD protocols would allow us to achieve positive secret key rates at high loss and high excess noise regimes of operation, which would have been otherwise impossible. This also keeps the prospect of running discrete-modulation CV-QKD over CV quantum repeaters alive.

中文翻译：

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量子剪刀增强的离散调制连续可变量子密钥分配

众所周知，量子剪刀作为非确定性放大器，可以提高高斯调制连续可变量子密钥分配（CV-QKD）在嘈杂和长距离工作状态下的性能。在这里，我们将此结果扩展到具有离散调制的非高斯 CV-QKD 协议。我们表明，通过使用适当的设置，在这种离散调制 CV-QKD 协议的接收器中使用量子剪刀将使我们能够在高损耗和高过量噪声操作制度下实现正密钥率，这将具有否则是不可能的。这也保持了在 CV 量子中继器上运行离散调制 CV-QKD 的前景。