Generation of a new bipartite coherent-entangled state and its applications

A new bipartite coherent-entangled state is introduced in the two-mode Fock space,which exhibits the properties of both a coherent state and an entangled state.The set of coherent-entangled states makes up a complete and partly nonorthogonal representation.A simple experimental scheme to produce the coherent-entangled state using an asymmetric beamsplitter is proposed.Some applications of the coherent-entangled state in quantum optics are also presented.     

Some applications of a new coherent-entangled state in two-mode Fock space

Using the technique of integration within an ordered product of operators,we find a new kind of coherent-entangled state(CES),which exhibits both coherent and entangled state properties.The set of CESs makes up a complete and partly nonorthogonal representation.Using a beam splitter,we propose a simple experimental scheme to produce the CES.Finally,we present some applications of CESs in quantum optics.     

Atomic coherent states as energy eigenstates of a Hamiltonian describing a two-dimensional anisotropic harmonic potential in a uniform magnetic field

In this paper we find that a set of energy eigenstates of a two-dimensional anisotropic harmonic potential in a uniform magnetic field is classified as the atomic coherent states |τ> in terms of the spin values of j in the Schwinger bosonic realization. The correctness of the above conclusions can be verified by virtue of the entangled state <η| representation of the state |τ>.     

THE AMPLITUDE-N-TH POWERED SQUEEZING OF AN ELECTROMAGNETIC FIELD IN THE MULTIPHOTON JAYNES-CUMMINGS MODEL INTERACTING WITH THE SUPERPOSITION STATE

We have studied the properties of the amplitude-N-th powered squeezing of an elec-tromagnetic field in the k-photon Jaynes-Cummings model of an atom initially being in the ground state and coupling with the superposition state. The results show that, under the condition of n≥k, where n is the photon number of the superposition state, the field exhibits not only the amplitude-N = n-th powered squeezing but also the amplitude-N = (n/2)-th powered squeezing for even n. The variations of the amplitude-N-th powered squeezing of the field with the powers N and k are discussed.     

双参数形变谐振子湮没算符高次幂的本征态

构造了双参数形变谐振子湮没算符高次幂aqsk(k≥3)的本征态,并利用qs积分给出了其完备性的证明.     

Finite-dimensional even and odd nonlinear pair coherent states and their some nonclassical properties

In this paper a new class of finite-dimensional even and odd nonlinear pair coherent states （EONLPCSs）, which can be realized via operating the superposed evolution operators D±（τ） on the state ｜q, 0）, is constructed, then their orthonormalized property, completeness relations and some nonclassical properties are discussed. It is shown that the finite-dimensional EONLPCSs possess normalization and completeness relations. Moreover, the finite-dimensional EONLPCSs exhibit remarkably different sub-Poissonian distributions and phase probability distributions for different values of parameters q, η and ξ.     

非共振相互作用系统中密度算符间距的演化

考虑到失谐量和原子初始相干性,给出了任意初态分布的二能级原子与任意单模场相互作用的密度算符间距的一般表达式.着重讨论了一个任意态分布的二能级原子与相干态光场相互作用时失谐量对密度算符间距演化的影响.结果表明：密度算符间距明显地依赖于失谐量的取值. 关键词：     

相干态Jaynes－Cummings模型中场的振幅N次方压缩

研究了一初始处于基态的二能级原子与相干态光场相互耦合的单光子Ｊａｙｎｅｓ－Ｃｕｍｍｉｎｇｓ（Ｊ－Ｃ）模型中场的振幅Ｎ次方压缩特性，并讨论了其压缩度随光场的初始平均光子数ｎ和压缩阶数Ｎ的变化．     

用Weyl对应与Wigner算符的途径构造表象

由Wigner算符的完备性和Weyl对应,我们推导出一个能获得纯态密度算符的新等式。借助此公式,可以方便快捷的构造出量子力学中一些有用的新表象。     

Quantum fluctuation in excited states of mesoscopic LC circuits at finite temperature

We discuss quantum fluctuation in excited states(named thermo number states) of mesoscopic LC circuits at a finite temperature.By introducing the coherent thermo state into the thermo field dynamics pioneered by Umezawa and using the natural representation of thermo squeezing operator we can concisely derive the fluctuation.The result shows that the noise becomes larger when either temperature or the excitation number increases.