Cascadable quantum time synchronization method

Abstract

The invention provides a cascading quantum time synchronization method. The method comprises the steps of: arranging a plurality of cascading stations in front of two stations needing time synchronization to form a cascading system, wherein the distance between every two adjacent stations does not exceed the action distance of quantum time synchronization; arranging a quantum light source and a quantum measurement device on each station to obtain photon arrival time between adjacent stations; based on a bidirectional time synchronization principle and a cross-correlation algorithm between frequency entangled two photons, calculating to obtain a clock difference between time frequency sources at the two ends of the cascade system by utilizing a photon arrival time sequence recorded by eachstation; and finally, adjusting the output time of the to-be-synchronized end by utilizing the measured clock error to realize time synchronization of the to-be-synchronized end and the source end. Onthe basis of fully utilizing the advantages of high accuracy and high stability of quantum time synchronization, the application distance of the quantum time synchronization is greatly expanded, so that the high-precision quantum time synchronization technology further meets the requirements of long-distance and high-precision time synchronization and transmission.

Description

technical field [0001] The invention belongs to the technical field of time frequency and relates to a time synchronization method. Background technique [0002] The current basic scientific research, major projects, national defense construction and the development of space technology have put forward higher and higher requirements for the accuracy of time synchronization. Quantum time synchronization is a new generation of time synchronization technology that has the greatest potential to greatly improve timing accuracy. Using quantum optical pulses with frequency entanglement characteristics and quantum coincidence detection technology, quantum time synchronization will make the existing time synchronization accuracy break through the limit of classical shot noise, and the accuracy can be increased by 2-3 orders of magnitude. Through the continuous improvement and maturity of solutions and technologies, high-precision quantum time synchronization technology will eventual...

AI Technical Summary

Problems solved by technology

It is difficult to generate high-brightness entangled light sources due to the generally inefficient nonlinear process

Affected by the loss of the transmission link, the two-photon source used for time delay measurement is inevitably attenuated sharply

At the same time, due to the unclonability of quantum light sources, the attenuated frequency entangled light source cannot be enhanced by classical optical amplification.

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