共查询到20条相似文献,搜索用时 15 毫秒
1.
增光子二模纠缠相干态的纠缠特性及其通过腔量子电动力学的制备 总被引:2,自引:1,他引:1
分析了增光子二模纠缠相干态的纠缠特性,得到共生纠缠度的解析表示式.结果表明:增光子二模纠缠相干态的共生纠缠度与叠加态的相位有非常灵敏的关系.提出了一种制备增光子相干态和增光子二模纠缠相干态的方法,其制备过程为首先把增光子相干态转化为相干态与真空态一种特殊的叠加态(叠加系数与相干态振幅有关),再通过位于高Q腔内的原子与经典激光场的相互作用,从而实现增光子相干态的制备.通过一个飞行原子先后与两个光腔中光场相互作用可以实现增光子二模纠缠相干态的制备. 相似文献
2.
3.
相干态的叠加态的量子统计性质 总被引:5,自引:2,他引:3
本文研究了相干态的叠加态的量子统计性质.结果表明,相干态的叠加态仅存在奇次幂的高阶压缩效应,而不存在偶次幂的高阶压缩效应.给出了高阶压缩和高阶反聚束效应与叠加系数间的函数关系.高阶压缩要求叠加系数的辐角取值满足cosθ>exp(-2|α|2),而高阶反聚束效应则要求0.5π<θ<1.5π.奇偶相干态的有关结果均作为特例应包含在本文的一般结论之中. 相似文献
4.
We investigate a new superposition of two coherent states via conditional measurement on a Mach-Zehnder interferometer (MZI). The resulted output state is obtained by using the superposition of two opposite coherent states with the arbitrary relative phase factors for the a-mode and vacuum state in the b-mode. It is shown that the angle of the phase shifter between the two arms of the MZI is a very important parameter in this new state.
相似文献5.
Summary In the recent years various and interesting superposition states of the quantized radiation field were investigated in the
literature, such as that involving two number states by Wodkiewiczet al.; that involving two coherent states by Hillery and Gerryet al.; that involving two squeezed states by Xinet al., etc. Here we study a general one-parameter superposition state which unifies those states and others in the literature,
all becoming a particularization of ours. General expressions characterizing the physical properties of the field are obtained.
The role played by the present superposition state as an alternative interpolating state is also discussed.
The authors of this paper have agreed to not receive the proofs for correction. 相似文献
6.
Production of the Superposition of Nonlinear Coherent States and Entangled Nonlinear Coherent States
In this paper, by using the parity operator as well as the nonlinear displacement-type operator, we define new operators which by the action of them on the vacuum state of the radiation field, superposition of two nonlinear coherent states and two-mode entangled nonlinear coherent states are generated. Also, we show that via the generalization of the presented method, the superposition of more than two nonlinear coherent states and n-mode entangled nonlinear coherent states can be generated. 相似文献
7.
Production of the Superposition of Nonlinear Coherent States and Entangled Nonlinear Coherent States
《理论物理通讯》2015,(9)
In this paper, by using the parity operator as well as the nonlinear displacement-type operator, we define new operators which by the action of them on the vacuum state of the radiation field, superposition of two nonlinear coherent states and two-mode entangled nonlinear coherent states are generated. Also, we show that via the generalization of the presented method, the superposition of more than two nonlinear coherent states and n-mode entangled nonlinear coherent states can be generated. 相似文献
8.
构造了一种由q变形相干态与q变形真空态叠加而成的态,研究了它的振幅k次方压缩性质和高阶反束特性,借助数值计算方法讨论了叠加系数、变形参数对这些特性的影响。 相似文献
9.
从相位分布和Wigner函数两个方面研究了任意两个相干态|β〉 and |mβeiδ〉的叠加态的量子统计性质.结果表明这种叠加态的非经典特性与β2,振幅系数m,相干态间的位相差δ以及叠加系数间的位相差都有关.当参量选择合适,这种叠加态存在着量子效应.计算了两个相干态等几率混合系综的相位分布和Wigner函数,经过与前者比较,结果表明由于相干项的存在,使得叠加态具有很好的量子力学行为. 相似文献
10.
11.
12.
We study optical schemes for generating both a displaced photon and a displaced qubit via conditional measurement. Combining one mode prepared in different microscopic states (one-mode qubit, single photon, vacuum state) and another mode in macroscopic states (coherent state, single photon added coherent state), a conditional state in the other output mode exhibits properties of a superposition of the displaced vacuum and a single photon. We propose to use the displaced qubit and entangled states composed of the displaced photon as components for quantum information processing. Basic states of such a qubit are distinguishable from each other with high fidelity. We show that the qubit reveals both microscopic and macroscopic properties. Entangled displaced states with a coherent phase as an additional degree of freedom are introduced. We show that additional degree of freedom enables to implement complete Bell state measurement of the entangled displaced photon states. 相似文献
13.
Shi-Biao Zheng Guang-Can Guo 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,1(1):105-107
We propose a method for preparing superpositions of coherent states of the motion of an ion in an anisotropic two-dimensional
trap, in which the ion is tightly bound in the y direction. In the scheme the ion is excited by two resonant laser beams with equal amplitude, propagating along the x and y directions, respectively. In the Dicke-Lamb limit, an initial coherent state of the ion motion can be converted into a superposition
of several coherent states on a circle through the laser-ion interactions and state-selective measurements on the ion.
Received: 30 May 1997 / Revised: 29 July 1997 / Accepted: 22 October 1997 相似文献
14.
A scheme is proposed for preparing the superposition of two-mode coherent states with controllable weighting factors along
a straight line for two-mode cavity field. In this scheme two-level atoms driven by classical field are sent through a two-mode
cavity initially in the vacuum state. Then the detection of the atoms make the cavity field be in a two-mode superpositions
of coherent states. 相似文献
15.
16.
Neergaard-Nielsen JS Nielsen BM Hettich C Mølmer K Polzik ES 《Physical review letters》2006,97(8):083604
We report on the experimental observation of quantum-network-compatible light described by a nonpositive Wigner function. The state is generated by photon subtraction from a squeezed vacuum state produced by a continuous wave optical parametric amplifier. Ideally, the state is a coherent superposition of odd photon number states, closely resembling a superposition of weak coherent states |alpha > - |-alpha >. In the limit of low squeezing the state is basically a single photon state. Light is generated with about 10,000 and more events per second in a nearly perfect spatial mode with a Fourier-limited frequency bandwidth which matches well atomic quantum memory requirements. The generated state of light is an excellent input state for testing quantum memories, quantum repeaters, and linear optics quantum computers. 相似文献
17.
两种特殊四态叠加多模叠加态光场的等N次幂H压缩 总被引:3,自引:0,他引:3
根据线性叠加原理,用多模相干态|{Zj*}〉q,|{-Zj*}〉q及其复共轭|{Zj*}〉q和|{-Zj*}〉q组成了两种四态叠加多模叠加态光场|Ψoe(4)Ⅵ〉q和|Ψ(4)oeⅦ〉q,利用多模压缩态理论研究了它们的等N次幂H压缩,结果发现:态|Ψoe(4)Ⅵ〉q和|Ψ(4)oeⅦ〉q具有完全相同的等N次幂H压缩规律;当压缩幂次N与腔模总数q之积,即qN为偶数时,态|Ψoe(4)Ⅵ〉q和|Ψ(4)oeⅦ〉q恒处于等幂次N-H最小测不准态或呈现"半相干态效应";当qN为奇数时,在不同条件下,态|Ψoe(4)Ⅵ〉q和|Ψ(4)oeⅦ〉q可以呈现三种不同状态:第一正交分量呈现等N次幂H压缩;第二正交分量呈现等N次幂H压缩; 可呈现"半相干态效应". 相似文献
18.
It is shown that two trapped ions interacting with laser beams resonant to the first red side-band of center-of-mass mode,in Lamb-Dicke regime and under rotating wave approximation,is described by a Jaynes-Cummings model.For the initial condition that the motional state of center-of-mass mode is in vacuum state and the internal state is prepared in a coherent superposition of states,coherence and squeezing for the vibratile motion of center-of-mass mode are discussed,particularly,a“weak” coherent state and a “weak” squeezed vacuum state are obtained.Collapse and revival are also observed in this type of initial condition. 相似文献
19.
Shahen Hacyan 《Foundations of Physics Letters》1996,9(3):225-233
The quantum sling is defined as a quantum harmonic oscillator with an abruptly vanishing frequency. It is shown in this article that a particle released by such a mechanism remains in acorrelated coherent state, i.e., a quantum state with the minimum dispersion in position and momentum allowed by the Schrödinger-Robertson uncertainty principle. This simple model permits to describe a Schrödinger-cat state (a quantum superposition of macroscopically distinguishable states) released by the sling. The result is a superposition of two correlated coherent states propagating in two opposite directions and with an interference term. 相似文献
20.
F. Plastina F. Piperno 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,5(3):411-415
We propose a simple method to obtain a superposition of coherent states on a circle, including Schr?dinger cat states as a
special case, via conditional measurement of the state of three level atoms interacting with a one mode cavity field. In the low amplitude
limit, very good approximation of Fock states can also be generated in this way.
Received: 8 October 1998 / Accepted: 30 October 1998 相似文献