Nonclassicality Of Several Quantum States And Their Decoherence Evolution

Since the birth and development quantum mechanics theory,it describes a new world to us and gradually integrates in to every field of our life.Quantum information,a new quantum technology combined with information theory and quantum mechanics,it has received extensive attention in today's society,the birth of this new technology makes the social information has diversified development.With the development of quantum information theory,the quantum decoherence effector the coupling between open quantum system and external environment has always been the focus of attention.In the past research,scientists have made considerable progress through unremitting efforts,but there are still some theoretical basis issues about quantum entanglement and quantum decoherence have not been improved.Solve the problem of decoherence and entangled in many areas that the quantum entanglement has the very vital significance in the aspect of quantum measurement.In the actual measurement,the measurement used in the process of measuring tool is inevitable,in the process of using the measuring tool will appear the interaction between it and the system.That is to say,it can produces entanglement between the measuring tools and systems,and the entanglement will affect the measurement.Therefore,with the development of quantum technology,the preparation of a stable coherent quantum state has become the basis of various quantum technology fields.However,quantum decoherence will appear in the preparation of quantum states,and quantum decoherence is an obstacle to the development of quantum technology.To Further improve the basic theory of quantum decoherence,the people research the evolution of quantum state in a single channel and explore the problem of decoherernce.The actual environment is complex and diverse,so the research of dual channel or even the multichannel quantum decoherence can be solving environment problems of theoretical basis.In this paper,we introduce the significance of studying the evolution of quantum state in two channels,the current development at home and abroad,and the normal product technology and thermal entangled state representations in the first chapter.In Section 2,we mainly introduce the evolution of quantum states simultaneously undergoing the damping noise and thermal noise.In Section 3,we introduce the evolution of quantum states simultaneously undergoing phase damping noise and amplitude damping noise.In this chapter compares the quantum states in the similarities and differences of two kinds of environment evolution.In Section 4,we generalize the nonclassical properties if quantum state.The quantum state R is a new quantum state prepared by the angular momentum operator and the introduction of a new unitary evolution operator.The Bose implementation of the angular momentum operator is as follows:(?) and (?) ,the relationship between the angular momentum operator:(?) .First of all,we observed the quantum statistical properties of the quantum state,as is known to all,the photon number distribution is to observe the quantum statistical properties of powerful tool,I calculated the photon number distribution.Since the oscillation of photon number distribution can be explained by the interference effect in phase space,the photon number distribution is considered to be a qualitative indicator of the non-classical nature of quantum states.So the photon number distribution P(7)n _a,n_b(8)is the necessary for the quantum state.In this section,we calculate the Neumann entropy of the quantum state to quantify the entanglement degree of the new quantum state.Finally,the nonclassical properties of quantum states are observed by Wigner function and its distribution under boundary conditions.The quantum interference properties and partial negative values are very valuable to describe the nonclassical properties of quantum states.