Research progress in quantum key distribution

Quantum key distribution (QKD) is a sophisticated method for securing information by leveraging the principles of quantum mechanics. Its objective is to establish a confidential key between authorized partners who are connected via both a quantum channel and a classical authentication channel. This paper presents a comprehensive overview of QKD protocols, chip-based QKD systems, quantum light sources, quantum detectors, fiber-based QKD networks, space-based QKD systems, as well as the applications and prospects of QKD technology.