Quantum communication is a new communication mode that uses quantum superposition state and entanglement effect to transmit information. Based on the three principles of uncertainty, measurement collapse and non cloning in quantum mechanics, it provides absolute security assurance that cannot be eavesdropped and cracked by computation. It is mainly divided into two types: quantum teleportation and quantum key distribution.

Quantum teleportation is based on the joint measurement of quantum entanglement pair distribution and bell state to realize the information transmission of quantum state. The key technologies of entanglement pair preparation, distribution and measurement in quantum teleportation need to be broken through. It is in the stage of theoretical research and experimental exploration, and there is still a big gap between them and practical application. Quantum key distribution, also known as quantum cryptography, realizes the secure quantum key sharing between the two communication parties by means of the transmission measurement of quantum superposition state, and then through the symmetric encryption system of one-time encryption, that is, both communication parties use a password of the same length as the plaintext for bit by bit encryption and decryption operations to achieve unconditional and absolutely secure secure communication. Quantum secret communication based on quantum key distribution has become a very potential technical means to ensure network information security in the future, and it is a hot spot in the field of quantum communication theory and application research.