双光子吸收过程中光场振幅平方压缩

本文由双光子过程主方程运用生成函数法,求得双光子吸收过程光场振幅平方压缩的表示式,讨论振幅平方压缩随无量纲时间τ,入射光场相位角θ及平均光子数|α|²的变化情况。双光子吸收过程是产生振幅平方压缩效应的有效途径。最后论证振幅平方压缩效应的独立性。 关键词：     

非等同两个原子与双模腔场相互作用模型中双原子偶极振幅平方压缩

本文研究了具有不同耦合系数的两个二能级原子与双模腔场相互作用系统中原子偶极振幅平方压缩随时间的演化规律.并讨论了两个原子与双模腔场的相对耦合常数(R=g1/g2)和腔场的初态对原子偶极振幅平方压缩的影响.     

Amplitude-Squared Squeezing in a Kerr-Nonlinear Blackbody

We find that amplitude-squared squeezing of the photon field is present in a new blackbody, namely, a Kerr- nonlinear blackbody. The squeezing effect decreases as temperature T increases. The amount of the amplitude-squared squeezing in a Kerr-nonlinear blackbody is much larger than the corresponding squeezing in normal blackbody, and the degree of amplitude-squared squeezing is much larger than the amplitude squeezing for the same range of parameters in a Kerr-nonlinear blackbody.     

Amplitude-squared squeezing of the photon field in a Kerr-nonlinear blackbody

We find the photon field in a Kerr-nonlinear blackbody is an amplitude-squared squeezed state. The squeezing effect decreases with increasing temperature T. The amount of the amplitude-squared squeezing in a Kerr-nonlinear blackbody is much larger than the corresponding squeezing in normal blackbody, and the degree of amplitude-squared squeezing is much larger than the amplitude squeezing for the same range of parameters in a Kerr-nonlinear blackbody. The frequency ω_k and parameter γ also have important influences on the amplitude-squared squeezing in a Kerr-nonlinear blackbody.     

真空态多光子Jaynes—Cummings模型中场的非经典性

研究了一初始处于原子相干态的二能级原子与真空场相互耦合的多光子Jaynes-Cummings模型中辐射场展示的亚泊松分布,压缩和振幅平方压缩等非经典效应.     

Amplitude-squared squeezing of superposition of coherent states

This paper discusses the amplitude-squared squeezing for the superposition of two coherent states with their phase differences being separately π/2, 3π/2, and π1, as well as for the superposition state of two pseudoclassical states. According to the analysis, it is found that the superposition state of two coherent states with their phase differences π/2 and 3π/2, and the superposition state of two pseudoclassical states both do exhibit the amplitude-squared squeezing. Also, some specific states are found to exhibit even stronger squeezing effects when relative phase of the superposition is equal to the average photon number. Amplitude-squared squeezing is dependent on the difference in phase between two coherent states.     

多光子非线性过程中的振幅平方压缩

本文研究了多光子非线性光学过程中的振幅平方压缩,证明了K光子么正算符Sk(z)(K>2)对非真空相干态的作用在—级近似下会产生振幅平方压缩.以及Sk(z)(K>2,K≠4)对真空态的作用不会产生振幅平方压缩.发现4个光子么正算符S4(z)对真空态的作用可以产生振幅平方压缩,这表明振幅平方压缩是一种独立于二阶压缩、反聚束以及亚泊松统计分布的新的光场非经典效应.     

叠加激发相干态的量子特性

构造了2个强度相同位相不同的激发相干态的叠加态,并通过数值计算研究了该叠加态的反聚束效应和振幅平方压缩效应随激发光子数m、光场强度x和相位差θ的变化,结果表明:随激发光子数m和光场强度x增大,该量子态的振幅平方压缩均会加深;压缩效应与相位差θ有密切的关系;随光场强度x的增大和激发光子数m的增大,其反聚束效应减弱.     

有限维Hilbert空间Roy型奇偶非线性相干态的振幅平方压缩

构造出了有限维Hilbert空间Roy型奇偶非线性相干态, 讨论了它们的正交归一完备性和振幅平方压缩效应. 研究表明, 在此空间中Roy型奇偶非线性相干态是归一完备的, 但不具有正交性; 当复参数相位角θ满足一定条件时它们存在振幅平方压缩效应, 同时导出了压缩条件与参数s,r以及函数f(n)之间的关系. 最后借助于数值计算, 发现对于5维(或7维)Hilbert空间中Roy型偶(或奇)非线性相干态, 当参数θ和Lamb-Dike参数η取某一给定值时, 在参数r变化的不同取值范围内, 它们均可以呈现振幅平方 关键词： 有限维Hilbert空间 Roy型非线性相干态 奇偶非线性相干态 振幅平方压缩     

Amplitude-squared squeezing of the generalized odd-even coherent states of the anharmonic oscillator in a finite-dimensional Hilbert space

This paper discusses the properties of amplitude-squared squeezing of the generalized odd-even coherent states of anharmonic oscillator in finite-dimensional Hilbert space. It demonstrates that the generalized odd coherent states do exhibit strong amplitude-squared squeezing effects in comparison with the generalized even coherent states.     

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。     

强场作用下二能级原子双光子过程中辐射场的压缩效应

本文采用数值计算方法研究了强场作用下二能级原子双光子过程中辐射场的压缩效应.结果表明:辐射场主要处于压缩态,并周期性地出现短时的非压缩效应,随着值的不断增大,场与原子的非线性耦合越来越强,压缩的最大深度不断加深.     

有限维希尔伯特空间q广义相干态振幅平方压缩

构造了有限维希尔伯特空间q变形非简谐振子广义相干态,研究了它的振幅平方压缩效应,结果表明,该量子态存在振幅平方压缩效应,并且给出了压缩条件与参数s,r,q之间的关系。     

两个二能级原子与真空辐射场相互作用中的偶极平方压缩

研究了两个二能级原子与真空辐射场相互作用中原子的偶极平方压缩效应。通过数值计算,讨论了原子与辐射场之间耦合常数相对大小值以及原子的初始相干性对偶极平方压缩效应的影响     

Amplitude-Squared Squeezing of Generalized q -Deformation Coherent States of a Non-harmonic Oscillator in a Finite-Dimensional Hilbert Space

Generalized q-deformation coherent states of a non-harmonic oscillator in a finite-dimensional Hilbert Space are constructed. Their amplitude-squared squeezing are discussed. The result shows that there are squeezing effects in these quantum states. The relationship between condition of squeezing and parameters S, r, q is found.     

压缩真空态与两原子相互作用过程中场的压缩性质

本文研究了两个二能级原子通过双光子跃迁与压缩真空态相互作用过程中辐射场的压缩和振幅平方压缩效应,讨论了两个二能级原子与光场的耦合常数的相对大小对它们的影响。     

Even and Odd Nonlinear Negative Binomial States

In this paper the even and odd nonlinear negative binomial states of the radiation field are introduced. These states interpolates between even (odd) number states and the even (odd) nonlinear coherent states. The Glauber second-order correlation function is calculated for these states. The squeezing phenomenon (normal and amplitude-squared squeezing), the quasi-probability distribution function Q-function, Wigner-function and the phase properties, are also discussed. Examination of the resonance fluorescence against the present state is given. It has been shown that the atomic inversion is sensitive to any variation in the even and odd nonlinear negative binomial number M and the nonlinearity parameter η.     

Squeezing and photon statistical effects in spontaneous and stimulated eight-wave mixing process

Eight-wave mixing is a process which involves absorption of four pump photons and emission of three probe photons of same frequency and a signal photon of different frequency. Squeezing is investigated in the fundamental mode in spontaneous and stimulated eight-wave mixing process using quantum mechanical approach. The presence of squeezing in field amplitude, amplitude-squared and amplitude-cubed in the fundamental mode has been probed. The dependence of squeezing on photon number is established with investigations into degree of squeezing in the first and higher order of field amplitude. The photon statistics of the field in the fundamental mode has also been investigated. It has been found that the field shows sub-Poissonian behaviour in the fundamental mode.     

Even and odd q-coherent states in a finite-dimensional basis and their squeezing properties

The even and odd coherent states of a deformed harmonic oscillator in a finites-dimensional Hilbert space are studied. It is shown that both fors even ands odd, the even q-coherent states exhibit quadrature and amplitude-squared squeezing, while the odd q-coherent states show an antibunching effect and amplitude-squared squeezing.     

交流斯塔克效应对简并喇曼过程场振幅N次方压缩的影响

用改进型有效哈密顿量方法研究简并喇曼过程中辐射场的振幅N次方压缩。发现如果场初始处于相干态,则它以后不会获得任何次方的压缩。如果场初始处于压缩真空态,则它以后可获N次方压缩。讨论了场涨落对次幂N、初场平均光子数n和压缩角ξ的依赖关系。