Unlock instant, AI-driven research and patent intelligence for your innovation.

Adjustable delay interferometer and quantum key distribution system

A time-delay interferometer and interferometer technology, applied in the field of quantum phase encoding, can solve problems that cannot be used to optimize the protocol key rate, and the interferometer has a large and complex structure, and achieves a simple structure, high length, and randomness Effect

Active Publication Date: 2022-03-01
杭州慧明量子通信技术有限公司
View PDF8 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In view of the above defects in the prior art, the present invention proposes an adjustable delay interferometer and a quantum key distribution system to solve the problem that the maximum delay of the interferometer in the prior art is determined, that is, the L value is fixed , and the fixed L value cannot be used to optimize the key rate of the protocol and the technical defect of the large and complex structure of the interferometer

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
  • Adjustable delay interferometer and quantum key distribution system
  • Adjustable delay interferometer and quantum key distribution system
  • Adjustable delay interferometer and quantum key distribution system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] The structure of the adjustable delay loop ADL is as follows: the polarization optical path selection module POSM is a first polarization beam splitter PBS1, the polarization rotation module PRM includes a first optical switch OS1 and a second optical switch OS2, and the first The first port, the second port, the third port and the fourth port of a polarization beam splitter PBS1 respectively serve as the first port, the second port, the third port and the fourth port of the polarization optical path selection module POSM, wherein the fourth port The polarization-maintaining optical fiber is 90° fusion-spliced; the second port of the first optical switch OS1 and the second port of the second optical switch OS2 are connected after 90° optical fiber fusion to form a path a, and the second port of the first optical switch OS1 The third port is directly connected to the third port of the second optical switch OS2 to form a path b, the path a and the path b have the same leng...

Embodiment 2

[0030] The structure of the adjustable delay circuit ADL is as follows: the polarization optical path selection module POSM is a second polarization beam splitter PBS2, and the polarization rotation module PRM includes a first circulator CIR1, a third polarization beam splitter PBS3 and a second polarization beam splitter PBS2. A phase modulator PM1, the first port, the second port, the third port and the fourth port of the second polarization beam splitter PBS1 respectively serve as the first port, the second port and the third port of the polarization optical path selection module POSM and the fourth port, wherein the polarization-maintaining fiber L1 of the fourth port is 90° fusion-spliced; the first port and the third port of the first circulator CIR1 are respectively used as the second port and the first port of the polarization rotation module PRM, so The second port of the first circulator CIR1 is connected to the first port of the third polarization beam splitter PBS3 ...

Embodiment 3

[0038] The structure of the adjustable delay loop ADL is as follows: the polarization optical path selection module POSM is a second circulator CIR2 and a fourth polarization beam splitter PBS4, and the polarization rotation module PRM includes a fifth polarization beam splitter PBS5, a fourth polarization beam splitter The two-phase modulator PM2 and the mirror M, the first port and the third port of the second circulator CIR2 are respectively used as the first port and the fourth port of the polarization optical path selection module POSM, and the fourth polarization beam splitter PBS3 The second port and the third port of the polarization optical path selection module POSM are respectively used as the second port and the third port; the second port of the second circulator CIR2 and the first port of the fourth polarization beam splitter PBS4 pass through the optical fiber L2 connected; the first port of the fifth polarization beam splitter PBS5 and the port of the mirror M a...

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

An adjustable delay interferometer comprises a first beam splitter BS1, a second beam splitter BS2, a polarization light path selection module POSM and a polarization rotation module PRM, an input port of the first beam splitter BS1 serves as an input port of the interferometer, a second output port of the first beam splitter BS1 is connected with a first port of the polarization light path selection module POSM, and a second output port of the polarization rotation module PRM is connected with a second port of the polarization light path selection module POSM. A fourth port of the polarized light path selection module POSM is connected with a second input port of the second beam splitter BS2 to form an unequal-arm Mach-Zehnder interferometer; the polarization light path selection module POSM and the polarization rotation module PRM form an adjustable delay loop ADL with basic delay T. The invention further discloses a quantum key distribution system. Compared with the prior art, large-range delay adjustment can be effectively achieved through polarization selection, the randomness and the high length of delay selection can be met, and meanwhile the key rate of a protocol can be maximized by optimizing the L value. The adjustable delay interferometer is simple in structure and stable in performance, and wide application of the RRDPS-QKD protocol can be guaranteed.

Description

technical field [0001] The invention relates to the technical field of quantum phase encoding, in particular to an adjustable delay interferometer and a quantum key distribution system. Background technique [0002] The quantum key distribution protocol (quantum key distribution, QKD) can provide unconditionally secure key distribution for long-distance communication parties, and its information theory security is guaranteed by the basic principles of quantum mechanics. Among them, Heisenberg's uncertainty principle guarantees that all eavesdropping behaviors will lead to changes in the quantum state transmitted in the channel, resulting in bit errors. Estimate the information volume of the original key obtained by the eavesdropper according to the bit error, so as to ensure the security of the communication process and achieve the longest transmission distance between the two parties. Signal perturbation is therefore a necessary monitoring factor to constrain potential inf...

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): H04L9/08H04B10/70
CPCH04L9/0852H04B10/70
Inventor 王士通王慎周宏飞
Owner 杭州慧明量子通信技术有限公司