Quantum conference key negotiation method and system based on coherent detection

Abstract

The invention discloses a quantum conference key negotiation method and system based on coherent detection, and the method comprises five stages: preparation, measurement, modulation, parameter estimation and post-processing, data under a time basis vector is used for extracting a quantum conference key, and data under an interference basis vector is used for calculating the contrast. The quantumconference key negotiation system comprises a continuous laser, an intensity modulator, a beam splitter and a single photon detector. The continuous laser generates phase-stable continuous light; theintensity modulator is used for carrying out pulse preparation on the passed optical signal and transmitting a pulse signal to the detection end; the beam splitter I and the beam splitter II are usedfor splitting an optical signal of the transmitting end; the beam splitter III is used for carrying out beam combination on the optical signals; the beam splitter IV and the beam splitter V form a Mach-Zehnder interferometer; the detector detects an optical signal at the detection end. The method is high in operability, experimental equipment is simple, phase randomization and different intensitymodulation are not needed, the safety risk is reduced, and the linear limitation of the code forming rate and the transmission distance in a relay-free quantum conference key agreement protocol is broken through.

Description

technical field [0001] The invention relates to the technical field of quantum communication, in particular to a coherent detection-based quantum conference key agreement method and system. Background technique [0002] Since entering the 21st century, with the rapid development of the Internet, information security has become increasingly important, and private communication between users has become one of the basic needs of the modern information society. With the development of various types of computers, especially the development of quantum computers, the computing power continues to increase, and the encryption algorithm based on computational complexity is no longer safe, and information security is facing increasingly severe challenges. Quantum communication came into being. Quantum communication is an emerging research field derived from the intersection of quantum mechanics and informatics. It uses the basic principles of quantum mechanics to ensure information se...

AI Technical Summary

Problems solved by technology

However, the required instruments and equipment are relatively complex, and the sending end needs a lot of equipment such as continuous laser, intensity modulator, phase modulator and signal attenuator, and complex operations such as phase randomization and different light intensity modulation are required, which increases the security risk

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