叠加的奇偶SU(1,1)相干态的统计性质

研究了将两个SU(1,1)相干态｜ζ,k〉和｜ζ,k〉叠加起来得到的新的量子态的统计性质．偶SU(1,1)相干态｜ζ,1/4〉和奇SU(1,1)相干态｜ζ,3/4〉分别对应于压缩真空态和压缩单光子数态．适当选取SU(1,1)态的相位角和叠加时的相对相位,得到的新的量子态比单个SU(1,1)相干态表现出大大增强的正交分量压缩和光子反群聚效应．也说明了怎样准备这样的叠加态． 关键词：     

双模SU(1,1)相干态场与V型三能级原子相互作用的动力学

研究了关联双模SU(1,1)相干态场与V型三能级原子的相互作用对原子动力学行为的影响及双模场的量子统计性质随时间的演化,证明了在双模SU(1,1)相干态光场作用下,原子的拉比振荡表现出与光场初态为双模压缩真空态或SU(2)相干态时的完全不同的特征。 关键词：     

Paul阱的含时广义SU(1,1)相干态

利用参量相关的Bogoliubov变换公式,导出描写Paul阱系统含时哈密顿的精确本征态--广义SU(1,1)相干态,讨论了关于这些态的粒子数涨落和平方振幅压缩特性.     

哈密顿算符是SU（1,1）和SU（2）算子含时线性组合量子系统的时间演变及…

研究了哈密顿算符是ＳＵ（１，１）和ＳＵ（２）算子线性组合且系数显含时间量子系统的时间演化。我们发现适当选取厄密不变量，不仅可得到统一的量子态时间演化封闭解，而且可得到时间演化幺正算符。用时间演化算符我们讨论了含时双光子压缩态和ＳＵ（１，１）相干态以及ＳＵ（２）压缩态的压缩性质。     

双模SU(1,1)相干态光场与V型三能级原子玻色-爱因斯坦凝聚体相互作用系统的量子性质

研究了双模SU(1,1)相干态光场与V型三能级原子玻色-爱因斯坦凝聚(BEC)相互作用系统中光场的量子相关性质、振幅平方压缩效应和原子激光压缩效应。结果表明,双模SU(1,1)相干态光场各模的二阶相干度不随时间变化,光场各模光子是反聚束的,呈现非经典效应,光场两模相关性是非经典相关。光场具有周期性的振幅平方压缩效应,讨论了光场相关参数和原子相关参数对压缩深度、压缩频率的影响。双模原子激光不易压缩,压缩深度取决于光场初态。     

二能级原子的混态SU(2)压缩

本文采用时间演化算符方法研究混态下二能级原子的SU(2)压缩行为,得出有光场相互作用下的混态原子的压缩比一般纯态原子算符的SU(2)压缩还要深,而且处于准基态下比在准激发态下的压缩要深得多的新结果。通过数值计算,讨论了原子能级布居的统计几率与压缩的关系。     

SU(1,1)群的非齐次逆微分实现

利用玻色振子的逆算符构造了SU(1,1)群的生成元和不可约表示的相干态,导出了SU(1,1)群的非齐次逆微分实现.     

自旋体系的一般SU(2)相干态

本文引进自旋体系的一般SU(2)相干态,讨论它的压缩特性、反聚束特性及其产生。证明当SU(2)群收缩到谐振子群时,一般SU(2)相干态转变成一般Glauber相干态,并给出有关的收缩结果。 关键词：     

单模加光子双模SU(2)相干态的非线性高阶差压缩

本文研究了单模加光子双模SU(2)相干态|M,ζ;m〉=Ama m|M,ζ〉的非线性高阶差压缩(即N次方X压缩)效应.数值计算结果表明:对于单模加光子双模SU(2)相干态,光场存在着非线性高阶差压缩??—N(=1,2,3,4,…)次方X压缩效应,且随着光场总光子数M的增加,N次方X压缩效应增强,但增大场模光子增加数m或增大N次方X压缩的压缩阶数N,N次方X压缩效应减弱.     

制备奇偶SU(2)相干态腔场纠缠态

利用一个参量频率转换过程，在腔中制备双模SU(2)相干态，然后在一系列全同的SU(2)相干态腔场注入一个A型三能级原子，使之与腔场的一个模发生拉曼相互作用，通过系列原子一腔场相互作用生成腔场一原子纠缠态，通过对原子进行选择性测量，可获得奇偶SU(2)相干态腔场纠缠态。     

SU(1,1) Lie Algebra Applied to the General Time-dependent Quadratic Hamiltonian System

Exact quantum states of the time-dependent quadratic Hamiltonian system are investigated using SU(1,1) Lie algebra. We realized SU(1,1) Lie algebra by defining appropriate SU(1,1) generators and derived exact wave functions using this algebra for the system. Raising and lowering operators of SU(1,1) Lie algebra expressed by multiplying a time-constant magnitude and a time-dependent phase factor. Two kinds of the SU(1,1) coherent states, i.e., even and odd coherent states and Perelomov coherent states are studied. We applied our result to the Caldirola–Kanai oscillator. The probability density of these coherent states for the Caldirola–Kanai oscillator converged to the center as time goes by, due to the damping constant γ. All the coherent state probability densities for the driven system are somewhat deformed. PACS Numbers: 02.20.Sv, 03.65.-w, 03.65.Fd     

SU(1,1)相干态光场的统计特性及其对原子动力学行为的影响

研究了Ｂａｒｇｍａｎ指标为ｋ＝１／４和ｋ＝３／４的两种ＳＵ（１，１）相干态光场的特性，证明了两种相干态具有不同的量子统计特性，并讨论了光场初始处于ＳＵ（１，１）相干态时，双光子Ｊａｙｎｅｓ－Ｃｕｍｍｉｎｇｓ（Ｊ－Ｃ）模型中，原子的动力学行为及粒子数反转随时间的演化，证明了与初始一般相干态光场不同，原子展现出特殊的周期振荡和脉冲行为。 关键词：     

SU(1,1) Coherent States for the Generalized Two-Mode Time-Dependent Quadratic Hamiltonian System

The SU(1,1) coherent states, so-called Barut-Girardello coherent state and Perelomov coherent state, for the generalized two-mode time-dependent quadratic Hamiltonian system are investigated through SU(1,1) Lie algebraic formulation. Two-mode Schrödinger cat states defined as an eigenstate of $\hat{K}_{-}^{2}The SU(1,1) coherent states, so-called Barut-Girardello coherent state and Perelomov coherent state, for the generalized two-mode time-dependent quadratic Hamiltonian system are investigated through SU(1,1) Lie algebraic formulation. Two-mode Schr?dinger cat states defined as an eigenstate of are also studied. We applied our development to two-mode Caldirola-Kanai oscillator which is a typical example of the time-dependent quadratic Hamiltonian system. The time evolution of the quadrature distribution for the probability density in the coherent states are analyzed for the two-mode Caldirola-Kanai oscillator by plotting relevant figures.     

Optical Fresnel Transform as a Correspondence of the SU(1,1) Squeezing Operator Composed of Quadratic Combination of Canonical Operators and the Entangled State

We study optical Fresnel transforms by finding the appropriate quantum mechanical SU(1,1) squeezing operators which are composed of quadratic combination of canonical operators. In one-mode case, the squeezing operator's matrix element in the coordinate basis is just the kernel of one-dimensional generalized Fresnel transform (GFT); while in two-mode case, the matrix element of the squeezing operator in the entangled state basis leads to the two-dimensional GFT kernel. The work links optical transforms in wave optics to generalized squeezing transforms in quantum optics.     

Maximally Entangled SU(1,1) Semi Coherent States

In this paper, we consider a special type of maximally entangled states namely by entangled SU(1,1) semi coherent states by using SU(1,1) semi coherent states(SU(1,1) Semi CS). The entanglement characteristics of these entangled states are studied by evaluating the concurrence.We investigate some of their nonclassical properties,especially probability distribution function,second-order correlation function and quadrature squeezing . Further, the quasiprobability distribution functions (Q-functions) is discussed.

     

双模非经典光场辐照下介观约瑟夫森结中超流的动力学行为

研究了直流偏置电压下介观约瑟夫森结在SU（1，1）双模相干态光场作用下超流的动力学行为、流压台阶和直流分量等特性．研究发现超流能够呈现明显的崩塌与复苏现象，对于经典电磁场和非耦合的双模相干态光场作用下的情况，超流不出现此现象，且其流压台阶结构与后两种情况也不相同． 关键词：     

两参数变形量子代数SU(1,1)q,s的相干态及其性质

利用SU(1,1)_q,s量子代数的两参数变形振子构造出归一化的SU(1,1)_q,s相干态,证明了SU(1,1)_q,s量子代数的表示基是正交的,并讨论了它的相干态的归一性和完备性。指出(SU(1,1)_q,s相干态的相干性受参数q、s的影响。     

Entropy squeezing and entanglement of the interaction between SU(1,1) and SU(2) quantum systems

The problem of the interaction between two quantum systems namely SU(1,1) and SU(2) is considered. Using the evolution operator technique, an exact solution of the wave function and consequently the density matrix are obtained. The entropy squeezing is examined and it has shown that, different values of the relative phase angle ? as well as the coupling parameter λ lead to different observation of the squeezing in the quadratures. In the meantime, we have shown that the entropy squeezing is also sensitive to the variation in the state angle θ, the detuning parameter Δ in addition to the excitation number m. Moreover, for a large value of the detuning parameter there is a weak entanglement between the atom and the quantum system and vice versa. Furthermore, we find that the Q-function is sensitive to the variation in the excitation number m in addition to the Bargmann index k where the nonclassical effect is pronounced for the even parity.