OAM measurement device-independent quantum key distribution system and method based on real-time tracking compensation

Abstract

The invention discloses an OAM measurement device-independent quantum key distribution system and method based on real-time tracking compensation. The system comprises a user end Alice, a user end Boband a measurement unit; the user end Alice and the user end Bob utilize strong pulse laser from a measurement unit to realize real-time monitoring and phase distortion compensation of a channel environment; and the measuring unit adopts an M-Z interferometer composed of a Dove prism to realize separation of odd / even orbital angular momentum order photons, and can carry out Bell state measurementon the photons with orbital angular momentum. The measurement device-independent quantum key distribution based on the orbital angular momentum is realized; a user uses an orbital angular momentum state to carry out coding; and the distribution system and method has the characteristics of high stability, high code forming rate and high expansibility.

Description

technical field [0001] The invention belongs to the technical field of quantum information and optical communication, and relates to a real-time tracking compensation OAM measurement equipment-independent quantum key distribution system and method. Background technique [0002] Since the first quantum key distribution protocol came out in 1984, quantum key distribution (Quantum Key Distribution, QKD) has been considered a very feasible technology in quantum information science. QKD allows two remote users (Alice and Bob) to generate keys with theoretically unconditional security according to the laws of quantum physics. However, in real-world settings, there is a gap between ideal models and actual devices. For example, an ideal QKD protocol requires an ideal single-photon source and detector to guarantee its safety. Judging from the current technology, ideal single photon sources and detectors are difficult to realize. The imperfections of these devices make QKD systems ...

AI Technical Summary

Problems solved by technology

Aiming at the problem of spectral inconsistency, people proposed a plug-and-play MDI-QKD (document: Liu, C.Q.at al. (2016). Polarization-Encoding-Based Measurement-Device-Independent Quantum Key Distribution with a Single Untrusted Source. ChinesePhysics Letters, 33(10).), but its modulation scheme has the problem that the measurement base reference frame does not completely match, which increases the bit error rate

In this regard, the recently proposed MDI-QKD scheme based on orbital angular momentum state (OAM) coding (document: Wang L, Zhao S M, Gong L Y, et al. Free-space measurement-device-independent quantum-key-distribution protocol using decoy states with orbital angular momentum[J].Chinese Physics B,2015,24(12):120307.), solved the problem of incomplete matching of the reference frame and reduced the bit error rate, but there was a problem of spectral inconsistency, And there is no good monitoring method and signal compensation method for the channel environment. Therefore, the performance of the weak signal quantum key distribution system is extremely susceptible to the influence of the external environment

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