平移激发压缩真空态及其性质

引入平移激发压缩真空态D(z)a\+\{+m\}S(r)|0〉,并讨论它的一些基本性质.利用正规 乘积内的积分技术,证明了其完备性.平移激发以后,与压缩真空态相比较,光子数分布 的振荡性质更加显著.与压缩真空态的光子总是聚束的性质不同,在平移参量|z|和激发 数m都较小时,平移激发压缩真空态的光子统计关联可以呈现反聚束效应.计算了它的准 概率分布函数(Q函数和Wigner函数),并讨论了它们对各参量的依赖关系,从Wigner函数可 以清楚地看出该量子态的非经典特性. 关键词：     

q变形对相干态的相位概率分布特性

通过推广Pegg和Barnett的相位算符和相位态到q变形的双模情况, 应用数值计算 研究了q变形对相干态的相位概率分布特性. 结果表明, q变形对相干态的相位概率分布受到相位参数、q参数和参数│ξ│的调节, 从而反映出不同的量子相干特性.     

激发双模压缩真空态的非经典特性

通过数值计算研究了激发双模压缩真空态a^+mb^+m|ξ>的非经典特性.结果表明:对于a^+mb^+m|ξ>,Cauchy-Schwartz不等式受到破坏;当取适当的压缩参量r(例如0.4～0.7)时,a^+mb^+m|ξ>呈现出正交分量的压缩和光子的亚泊松分布,而且压缩程度和亚泊松特性都随m的增大而有所增强.     

测量相位算符在压缩热场态中的压缩效应

利用Bannett和Pegg提出的测量相位算符讨论了压缩热场态中测量相位算符的压缩效应。结果表明测量相位算符在压缩热场态中存在CS类压缩，压缩特性与相干态参数幅角θ、平均光子数n^-和压缩参量r有密切的关系。随着n^-和r的增大，CS类压缩效应逐渐减弱，直至完全消失。另有计算表明测量相位算符在压缩热场态中不存在CN和SN类压缩。     

退激发压缩真空态及其特性

利用退激发压缩真空态归一化函数的产生函数, 获得了归一化的退激发压缩真空态. 借助于此态的归一化常数和中介表象理论, 我们得到了退激发压缩真空态的量子Tomogram函数和一些新的数学公式.     

利用PPKTP晶体产生真空压缩态及其Wigner准概率分布函数的量子重构

通过光学腔内置周期极化磷酸氧钛晶体的连续光学参量振荡器,以532nm光场为抽运场,产生1064nm的真空压缩态光场,利用平衡零拍探测技术得到3.41dB的实测压缩度,并采用量子层析技术重构出真空压缩态光场在相空间的Wigner准概率分布函数. 关键词： 真空压缩态光场 光学参量振荡器 量子层析 Wigner准概率分布函数     

非线性压缩单光子态的位相概率分布

利用f-谐振子的产生和湮灭算符的逆算符，构造了两个非线性压缩单光子态，并借助于Pegg—Barnett位相算符公式和数值计算方法，研究了它们的位相概率分布。结果表明，两个非线性压缩单光子态的位相概率分布不同；与通常的压缩单光子态、非线性压缩真空态不同，在这两个非线性压缩单光子态中，其位相概率分布能明显地反映出不同的量子位相信息和干涉特性。     

双模激发压缩真空态的维格纳函数

利用纠缠态表象下的维格纳(Wigner)算符,构造了双模激发压缩真空态的维格纳函数,并根据该函数在相空间ρ-γ中随参量m,n和r的变化关系,讨论了双模激发压缩真空态的量子干涉特性和压缩效应。结果表明,对于参量m,n不同的取值,双模激发压缩真空态的量子干涉效应的强弱不同;而对于不同的压缩参量r,双模激发压缩真空态呈现出不同程度的压缩效应。最后,根据双模激发压缩真空态的维格纳函数的边缘分布,阐明了此维格纳函数的物理意义。     

基于平移压缩真空态的强反聚束光场

具有反聚束特性的非经典光场是量子信息与量子光学的重要资源。基于非线性光学的量子干涉效应,通过将压缩真空态与特定相位的相干态在光学分束器上合成的方法获得平移压缩真空态,对压缩度和相干分量进行独立控制以获得反聚束。本文结合实验系统参数,理论研究了压缩真空态的压缩度和相干态的幅度对实验产生反聚束光场的影响。在最优化平移条件下,我们分析了系统总效率、背景噪声,以及Hanbury Brown-Twiss(HBT)与Double HBT测量方法对反聚束光场g⁽(2))(0)测量的影响,并讨论了误差为零处相应量子态的g⁽(2))(0)值和平均光子速率。     

叠加激发双模压缩真空态的量子统计特性(英文)

从激发双模压缩真空态a^+mb^+m|ξ>出发构造了叠加态|Ψ>,研究了|Ψ>的量子统计特性.结果表明:在一定的条件下,随着相位差的变化,叠加态|Ψ>的平均光子数出现类似于Rabi振荡的崩塌与复原现象,而且与单个激发双模压缩真空态a^+mb^+m|ξ>相比,在叠加态|Ψ>中光场的相位压缩和亚泊松光子统计特性都得到了加强.     

Husimi Functions of Excited Squeezed Vacuum States

Based on the Husimi operator in pure state form introduced by Fan et al., which is a squeezed coherent state projector, and the technique of integration within an ordered product （IWOP） of operators, as well as the entangled state representations, we obtain the Husimi functions of the excited squeezed vacuum states （ESVS） and two marginal distributions of the Husimi functions of the ESVS.     

Husimi Functions of Excited Squeezed Vacuum States

Based on the Husimi operator in pure state form introduced by Fan et al., which is a squeezed coherent state projector, and the technique ofintegration within an ordered product (IWOP) of operators, as well as theentangled state representations, we obtain the Husimi functions of theexcited squeezed vacuum states (ESVS) and two marginal distributions of theHusimi functions of the ESVS.     

Some Properties of Two-mode Displaced Excited Squeezed Vacuum States

In this paper, two-mode displaced excited squeezed vacuum states （TDESVS） are constructed and their normalization and completeness are investigated. Using the entangled state representation and Weyl ordering form of the Wigner operator, the Wigner functions of TDESVS are obtained and the variations of Wigner functions with the parameters m, n and r are investigated. Besides, two marginal distributions of Wigner functions of TDESVS are obtained, which exhibit some entangled properties of the two-particle＇s system in TDESVS.     

Casimir Force of Squeezed Vacuum

The Casimir force of the quantized electromagnetic field in the squeezed vacuum state is calculated betweena pair of parallel perfectly conducting plates at zero temperature.     

Two-Mode Excited Squeezed Vacuum State and Its Properties

In this paper, the two-mode excited squeezed vacuum state (TESVS) is studied by using the statistical method. By calculating the normalization of the TESVS, a new form of Jacobi polynomials and some new identities are obtained. The photon number distribution of the TESVS is given and it is a simple form of Jacobi polynomials. Using the entangled state representation of Wigner operator, the Wigner function of the TESVS is obtainded and the variations of the Wigner function with the parameters m, n, and r are discussed. Here from the phase space point of view the TESVS can be well interpreted and described.     

Casimir Force of Squeezed Vacuum

The Casimir force of the quantized electromagnetic field in the squeezed vacuum state is calculated between a pair of parallel perfectly conducting plates at zero temperature.     

Husimi Function of Excited Squeezed Vacuum State

The q-p phase-space distribution function is a popular tool to study semiclassical physics and to describe the quantum aspects of a system. In this paper by using the pure state density operator formula of the Husimi operator Δ_h(q,p;κ)=|p,q〉_κκ〈p,q| we deduce the Husimi function of the excited squeezed vacuum state. Then we study the behavior of Husimi distribution graphically.     

增光子压缩真空态的反群聚效应

本文讨论了压缩真空态在玻色湮灭算符的逆算符及玻色产生算符作用下的光子反群聚性质. 结果表明, 在两种情况下所得到的增光子压缩真空态都呈现出反群聚效应, 但前者呈现的反群聚效应与所增加的光子数k以及压缩参数的取值区间有关, 而后者则在相同的压缩参数取值区间内呈现出反群聚效应, 与增加的光子数k无关.