Research On Entanglement Detection Based On Quantum Measurement

Quantum information is the product of the combination of quantum mechanics and information science.It is a new subject in the research of information processing.The emergence of quantum information theory brings many new research topics,such as quantum cryptography,quantum teleportation and quantum dense coding.These researches combine mathematics,physics,computing,information and many other fields closely.Starting from quantum mechanics theory,quantum entanglement becomes an important subject.For a given quantum state,how to judge whether it is entangled? In fact,this is a NP-hard problem.However,many scientists have obtained lots of criteria for detecting entanglement,which has accelerated the development of quantum communications and quantum computing.As an important resource of quantum information and quantum computing,it is very important to study quantum entanglement in depth.Based on the existing methods of quantum entanglement detection,this paper is devoted to obtaining a more effective separable criterion.First,a series of basic knowledge of quantum information are introduced.Then,some basic concepts about quantum entanglement are reviewed,including the definition,characteristics,detection of entanglement and the quantum entanglement.Based on two kinds of measurement(MUMs,GSIC-POVMs),this paper proposed four new entanglement detection criteria.The main idea is to introduce a new item on the basis of the traditional measurement.The new entanglement detections are used to detect the entanglement of the quantum state,which is a very fine analysis work.This is to improve and optimize the related criteria and improve the efficiency of the entanglement detection.Finally,by studying the rearrangement concept of the operator,the rearrangement criterion of the bipartite quantum state is extended to the multipartite quantum state,and acriterion for detecting the multibody quantum entanglement is proposed,which is superior to the relevant criterion.