Double-scanning 4-intensity MDI-QKD method and system based on corrected coherent state light source

A dual-scan, light source technology, applied in key distribution, can solve the problems of code rate limitation and low single-photon rate, and achieve a wide range of effects.

Pending Publication Date: 2022-04-05
JINAN INST OF QUANTUM TECH
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the low single-photon rate of the existing widely used weak coherence state (WCS) light source, the coding rate of the system using this light source is naturally limited

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Double-scanning 4-intensity MDI-QKD method and system based on corrected coherent state light source
  • Double-scanning 4-intensity MDI-QKD method and system based on corrected coherent state light source
  • Double-scanning 4-intensity MDI-QKD method and system based on corrected coherent state light source

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0057] Such as figure 1 As shown, a dual-scan 4-intensity MDI-QKD system based on a modified coherent state light source includes three parts: Alice, Bob, and Charlie. Alice and Bob, as the sender, have exactly the same structure, and emit light to the third party Charlie at the same time pulse. Charlie, as the measurement party, measures the received light pulse pairs, and Charlie can also be an untrustworthy eavesdropper (Eve). This scheme is suitable for phase encoding system.

[0058] The workflow of this system includes:

[0059] (1) When the MCS light sources of Alice and Bob emit photons, it is necessary to ensure that the single photons on both sides have the same frequency, so that the two photons arriving at Charlie will interfere. In this embodiment, it can be implemented by using the frequency locking technology of the lasers on both sides.

[0060] (2) The MCS light sources of Alice and Bob respectively modulate and send N light pulses, and the light pulses at...

Embodiment 2

[0081] The difference between this embodiment and embodiment one is:

[0082] Such as figure 2 As shown, for the polarization encoding system, after the two-photon interference occurs at the beam splitter BS of the measurement party Charlie, Charlie performs the Bell state measurement, and uses two polarization beam splitters PBS and four single-photon detectors after the beam splitter BS The device SPD performs interferometry on the four polarization states.

Embodiment 3

[0084] A dual-scan 4-intensity MDI-QKD method based on a modified coherent state light source, from the perspective of the sender, includes the following steps:

[0085] Use the modified coherent state light source to modulate and send multiple light pulses. When sending light pulses, they are randomly modulated into different quantum states with a certain probability, and the parameters of the vacuum state and decoy state are numerically limited, and the parameters of the signal state are not limited. ;

[0086] Receive published measurements and screen your own bits;

[0087] The final key is obtained by post-processing the filtered bit string.

[0088] Specifically, there are two senders, and the optical pulses sent by each have the same photon frequency.

[0089] Specifically, the quantum state includes the vacuum state of the corresponding sender, the first decoy state and the second decoy state under the X basis vector, and the signal state under the Z basis vector.

...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a double-scanning 4-intensity MDI-QKD method and system based on a corrected coherent state light source, a sender uses the corrected coherent state light source to modulate and send a plurality of light pulses, when the light pulses are sent, the light pulses are randomly modulated into different quantum states according to a certain probability, numerical value limitation is carried out on vacuum state and decoy state parameters in the light pulses, and the light pulses are sent to the receiver; signal state parameters are not limited; the measuring party performs Bell state measurement on the received optical pulse and publishes a measurement result; the sender receives the published measurement result, screens its own bits, and post-processes the screened bit string to obtain a final key; according to the invention, a corrected coherent state light source is adopted, and different parameters are reasonably set when a signal state and a decoy state are sent, so that a single photon event with higher probability can be obtained and a higher key rate can be obtained.

Description

technical field [0001] The invention belongs to the technical field of quantum security communication, and in particular relates to a double-scan 4-intensity MDI-QKD method and system based on a modified coherent light source. Background technique [0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art. [0003] Measurement device-independent quantum key distribution (MDI-QKD) system can defend against any side-channel attack at the detection end, and it is easy to combine with the decoy state method, which has broad application prospects. However, in practical applications, the key rate of the decoy-state MDI-QKD system is affected by the finite code length effect and decreases rapidly with the increase of distance. [0004] In recent years, many studies have devoted themselves to improving the key rate and coding distance of the system, and have achieved considerable results...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H04L9/08
Inventor 王向斌姜聪张万里周飞
Owner JINAN INST OF QUANTUM TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products