Speeding, efficient-raising and dilatating method for quantum cipher key distribution

Abstract

The present invention belongs to the field of quantum cipher communication technology. Compared with traditional quantum cipher key scheme based on N groups of measuring base, the said method has thefollowing features. The selection of the base is controlled with one string of repeated control codes to change the selection of the base from random one to determined one end to the interceptor, thecontrol codes are cipher key string. Thus, the quantum bit utilization is raised from original (1 / N)x100% to near 100%. Omitting the step of comparing the base in both sides and substituting simplified encoding with all capacity encoding raise the information carrying amount each quantum state from original quantum bit to log2(2N) quantum bit. So, the total bit information transmission efficiencyis raised by at least N / log2(2N) times.

Description

technical field [0001] The method for accelerating full effect and capacity expansion in quantum key distribution belongs to the technical field of quantum secret communication. Background technique [0002] Different from traditional cryptography, quantum cryptography communication is the product of the combination of cryptography and quantum mechanics. It uses quantum states as information carriers and uses some principles of quantum mechanics to protect information. Usually, the two sides of the communication use the quantum state as the information carrier, use the principle of quantum mechanics, transmit through the quantum channel, and establish a shared key between each other, which is called Quantum Key Distribution-QKD. Its security is It is guaranteed by the "Heisenberg Uncertainty Relation" (or Uncertainty Principle) and "Single Quantum Unreproducible Theorem" (also called Unclonable Theorem of Unknown Quantum State - Non-cloning Theorem) in quantum mechanics. Qu...

AI Technical Summary

Problems solved by technology

The qubits in the transmission process cannot all be used for the quantum key, only no more than 50% of the qubits can be used, and the utilization rate of the qubits is low

At the same time, in terms of encoding capacity, two quantum states can only represent 1 classical bit of information, and four quantum states can only represent two codes of "0" and "1", and the encoding capacity is also low.

In addition, in order to obtain 1 bit of quantum information, at least 2 bits of classical information need to be exchanged, that is, Bob needs to tell Alice which quantum states he uses  basis for measurement, and which ones choose  basis for measurement; Alice needs to tell Bob which Some quantum states use the same basis, so the overall bit information transmission efficiency is also low (≤25%)

[0016] Other quantum key transmission schemes based on multiple sets of measurement bases, such as 4+2 scheme, six-state scheme, etc., are similar in principle to the BB84 scheme, and they all use random selection of measurement bases to ensure the security of the quantum key transmission process , so the defect is also similar to the BB84 quantum key transmission scheme, that is, low efficiency, low communication capacity, and low overall bit information transmission efficiency

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