Quantum cryptography is arguably the fastest growing area in quantum information science. Novel theoretical protocols are designed on a regular basis, security proofs are constantly improving, and experiments are gradually moving from proof-of-principle lab demonstrations to in-field implementations and technological prototypes. In this review, we provide both a general introduction and a state of the art description of the recent advances in the field, both theoretically and experimentally. We start by reviewing protocols of quantum key distribution based on discrete variable systems. Next we consider aspects of device independence, satellite challenges, and high rate protocols based on continuous variable systems. We will then discuss the ultimate limits of point-to-point private communications and how quantum repeaters and networks may overcome these restrictions. Finally, we will discuss some aspects of quantum cryptography beyond standard quantum key distribution, including quantum data locking and quantum digital signatures.

中文翻译：

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量子密码学的进展

量子密码学可以说是量子信息科学中发展最快的领域。定期设计新的理论协议，安全证明不断改进，实验逐渐从原理验证实验室演示转向现场实施和技术原型。在这篇评论中，我们提供了对该领域最新进展的一般介绍和最先进的描述，包括理论和实验。我们首先回顾基于离散变量系统的量子密钥分发协议。接下来我们考虑设备独立性、卫星挑战和基于连续变量系统的高速率协议等方面。然后我们将讨论点对点私人通信的最终限制以及量子中继器和网络如何克服这些限制。最后，我们将讨论标准量子密钥分发之外的量子密码学的一些方面，包括量子数据锁定和量子数字签名。