共查询到20条相似文献,搜索用时 61 毫秒
1.
采用Negativity熵来度量两个子系统间的纠缠,利用数值计算方法研究了简并Λ型三能级原子和简并V型三能级原子与耦合腔共振相互作用系统中原子之间、腔场之间和原子与腔场间的纠缠特性.给出了系统初始激发数为1时系统态矢的演化公式;讨论了腔场间的耦合系数变化对纠缠特性的影响.研究结果表明:随腔场间的耦合系数增大,原子间的纠缠增强,腔场间的纠缠减弱. 相似文献
2.
研究了由一个Λ型三能级原子、一个V型三能级原子和光纤连接的双模腔构成的系统,给出了系统态矢的演化. 采用部分转置密度矩阵的负本征值来描述两个子系统间的纠缠,利用数值计算方法研究了原子与原子之间和腔场与腔场之间的纠缠特性. 讨论了光纤模与腔场间的耦合强度对纠缠特性的影响. 研究结果表明:随光纤模与腔场间的耦合强度增强,原子间的纠缠和腔场间的纠缠均增强.
关键词:
量子光学
原子-腔-光纤复合系统
三能级原子
量子纠缠 相似文献
3.
Quantum entanglement in the system of a moving V-type three-level atom interacting with the SU(1,1)-related coherent fields 下载免费PDF全文
In a system with a moving V-type three-level atom interacting with
the SU(1,1)-related coherent fields,
we investigate the entanglement between the moving three-level atom
and the SU(1,1)-related coherent fields by
using the quantum-reduced entropy, and that
between the SU(1,1)-related
coherent fields by using the quantum relative
entropy of entanglement. It is shown that the two kinds of entanglement
are dependent on the atomic motion and
exhibit the periodic evolution with a
period of 2π/p. The maximal atom--field qutrit entanglement
state can be prepared, and the entanglement preservation
of the SU(1,1)-related coherent fields
can be realized in the interacting process
via the appropriate selection of system
parameters and interaction time. 相似文献
4.
5.
S. Roshan Entezar 《Optics Communications》2009,282(6):1171-1174
In this paper, the effect of quantum interference on the entanglement of a driven V-type three-level atom and its spontaneous emission field was investigated by using the quantum entropy. The results indicate that, in the absence of quantum interference the atom and its spontaneous emission field are always entangled at the steady-state. But, in the presence of full quantum interference their steady-state entanglement depends on the atomic parameters. Specifically, with appropriate atomic parameters they can be entangled or disentangled at the steady-state. We realized that the steady-state entanglement is due to completely destructive nature of quantum interference. On the contrary, the steady-state disentanglement is due to instructive nature of quantum interference. 相似文献
6.
Wen-Xing Yang Ai-Xi Chen Ting-Ting Zha Yanfeng Bai Ray-Kuang Lee 《Central European Journal of Physics》2014,12(10):737-743
We demonstrate the generation of two-mode continuous-variable (CV) entanglement in a V-type three-level atom trapped in a doubly resonant cavity using a microwave field driving a hyperfine transition between two upper excited states. By numerically simulating the dynamics of this system, our results show that the CV entanglement with large mean number of photons can be generated even in presence of the atomic relaxation and cavity losses. More interestingly, it is found that the intensity and period of entanglement can be enhanced significantly with the increasing of the atomic relaxation due to the existence of the perfect spontaneously generated interference between two atomic decay channels. Moreover, we also show that the entanglement can be controlled efficiently by tuning the intensity of spontaneously generated interference and the detuning of the cavity field. 相似文献
7.
We present a detail study of the evolution of nonlocal correlations of an interacting quantum system comprising a three-level atom and a field mode initially prepared in a squeezed vacuum state with added photons. We compare the dynamical behavior of the quantum phase and entanglement by varying the number of photons added to the squeezed vacuum state. Furthermore, we examine the influence of the added-photon number and the squeeze parameter on the dynamical behavior of entanglement, quantum phase, and nonclassical properties of the field. Moreover, we explore the link between the quantum phase and the nonlocal correlation. Finally, we introduce an effective method to generate and maintain a high level of entanglement for this quantum system based on precise parameter ranges. 相似文献
8.
双模纠缠相干光场与Ⅴ型三能级原子相互作用系统的原子偶极压缩效应 总被引:2,自引:2,他引:0
采用求解Schrodinger方程和数值计算方法,研究了双模纠缠相干光场与Ⅴ型三能级原子相互作用过程中原子偶极算符的压缩效应,结果表明:此压缩效应与双模纠缠光场的纠缠程度、失谐量相关联. 相似文献
9.
双模纠缠相干光场与V型三能级原子相互作用系统的原子偶极压缩效应 总被引:6,自引:3,他引:3
采用求解Schroedinger方程和数值计算方法,研究了双模纠缠相干光场与V型三能级原子相互作用过程中原子偶极算符的压缩效应,结果表明:此压缩效应与双模纠缠光场的纠缠程度、失谐量相关联。 相似文献
10.
本文提出利用V-型三能级原子与双模腔场的双光子大失谐相互作用制备W纠缠态,该方案要求三个三能级原子和一个双模腔场,第一个与腔场作用的原子最初处于激发态,第二个和第三个原子均处于基态,腔场最初处于真空态,合适地选择原子与腔场之间的相互作用时间即可获得三原子W纠缠态.并且此方案可以推广至多原子W纠缠态和多腔场W纠缠态的制备;通过计算共生纠缠度研究系统中态的纠缠演化以及热纠缠现象. 相似文献
11.
张蕾 《原子与分子物理学报》2016,33(6)
本文提出利用 型三能级原子与双模腔场的双光子大失谐相互作用制备W纠缠态,该方案要求三个三能级原子和一个双模腔场,第一个与腔场作用的原子最初处于激发态,第二个和第三个原子均处于基态,腔场最初处于真空态,合适地选择原子与腔场之间的相互作用时间即可获得三原子W纠缠态。并且此方案可以推广至多原子W纠缠态和多腔场W纠缠态的制备;通过计算共生纠缠度研究系统中态的纠缠演化以及热纠缠现象。 相似文献
12.
文章利用V-型三能级原子与双模腔场双光子共振相互作用,提出了一种纠缠交换的方案制备最大纠缠态,此方案不需要Bell基测量,只需对单个原子进行测量,就能实现初始没有直接相互作用的原子与腔场之间产生纠缠,合适选择原子与腔场之间的相互作用时间可获得具有最大保真度以及成功几率的最大纠缠态,另外,还讨论了该方案的实验可行性. 相似文献
13.
In this paper, we study the dynamics of entanglement between three-level atom and optical field, initially prepared in the squeezed coherent state. We discuss the dynamical behavior of the geometric phase and entanglement, measured by the von Neumann entropy, with and without rotating wave approximation during the time of evolution. The effect of the squeezing and detuning parameters on the evolution of entanglement and geometric phase will be examined. We find that the squeezing and detuning parameters play a central role on the evolution of the geometric phase and nonlocal correlation between the field and the three-level atom. Moreover, we show that the dynamics of the system in the presence of rotating wave approximation has a richer structure compared with the absence of rotating wave approximation. 相似文献
14.
双模纠缠相干光场与V型三能级原子相互作用系统的光子统计性质 总被引:11,自引:7,他引:4
本文采用求解Schrodinger方程和数值计算方法,研究了双模纠缠相干光场与三能级原子相互作用系统的光子统计性质,结果表明:此性质与双模纠缠相干光场的纠缠程度、失谐量、双模光的平均光子数和原子的初态相关联. 相似文献
15.
The system of an atom couples to two distinct optical
cavities with decoherence is studied by making use of a dynamical
algebraic method. We adopt the concurrence to characterize the
entanglement between atom and cavities or between two optical
cavities in the presence of the phase decoherence or dissipation.
It is found that the entanglement between atom and cavities can be
controlled by adjusting the detuning parameter. We show that even
if the atom is initially prepared in a maximally mixed state, it
can also entangle the two mode cavity fields. Finally, the Bell
violation of the cavity fields is discussed, and it is shown that
both the detuning and decoherence can deteriorate the maximal
amount of violation of Bell inequality for two mode cavity fields
during the evolution. 相似文献
16.
K. J. M. Abu Alnaja S. E. Waheed S. Abdel-Khalek 《Journal of Russian Laser Research》2016,37(3):219-226
We present a model of interaction between a four-level atom and the cavity field initially prepared in the coherent state in the presence of the phase damping effect. We discuss the atom–field entanglement and statistical properties under the damping effect in view of numerical calculations. We use the Mandel parameter as a quantifier of the statistical properties of the field; moreover, we study the different effects of the collective parameters in the master equation on the dynamical behavior of the field statistical properties and the entanglement measured by the negativity. Finally, we explore the link between the entanglement and statistical properties in view of the numerical results during the time evolution. 相似文献
17.
Nour Zidan 《Physica A》2012,391(1-2):401-409
By using an algebraic dynamical approach, the atom–field bipartite system in mixed state is employed to investigate the influence of intrinsic decoherence and Stark shift on the partial entropy change and the entanglement. It is shown that, quality of the partial entropy is improved significantly by introducing the intrinsic decoherence and(or)Stark shift. In addition, by the concept of the lower bound of the concurrence, the entanglement between the atom and the field under the influences of intrinsic decoherence and Stark shift is also presented. 相似文献
18.
In this paper the time evolution of von Neumann entropy, as a measure of entanglement between V-type three-level atoms and the union of a two-mode field, is studied. The atom–field interaction is assumed to occur in a Kerr-type medium with an intensity-dependent coupling. Introducing a Casmir operator whose eigenvalues, N, give total excitations in the system and commutes with the governing Hamiltonian, it is concluded that the latter is block-diagonal with ever growing dimensions. As we shall show, however, each block consists of two 2 × 2 blocks while all the others, (N??1) in number, are 3 × 3. We then proceed to analytically calculate the time-evolution operator which is also block-diagonal, each block with the same properties as that of the Hamiltonian. Our calculations show that, as expected, the atom–field entanglement oscillates which, depending upon the initial state, exhibits the phenomenon of collapse revivals. It is further shown that collapse revivals occur whenever both 2 × 2 blocks are involved in the time evolution of the system. Properties of such behaviour in the entanglement are also discussed in detail. 相似文献
19.
C.-Z. Wang C.-X. Li G.-C. Guo 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,37(2):267-273
In this paper we consider a quantum optics model where two-mode
quantum light cavity with Kerr-like medium is coupled to an atom via
two-photon process. The dynamical evolution of the system is studied
in terms of entanglement measured by quantum relative entropy. The
entanglements for the different bipartite partitions of the system,
i.e., atom-two modes, mode-mode, mode-(atom+mode), are calculated
explicitly and interesting trade-off relations between the different
kinds of entanglement can be observed in different cases. The
results show the entanglement between mode-mode is generally out of
phase with that between atom and two modes, even though the two
modes do not interact directly, and the Kerr-like medium prevents
the atom and two modes from entangling. 相似文献
20.
F. Kheirandish S. J. Akhtarshenas H. Mohammadi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,57(1):129-140
Entanglement dynamics of an open two-qubit anisotropic
XY Heisenberg system is investigated in the presence of an
inhomogeneous magnetic field and spin-orbit interaction. We
suppose that each qubit interacts with a separate thermal
reservoir which is held in its own temperature. The asymptotical
and the dynamical behavior of entanglement are analyzed. To
distinguish between entanglement induced by the environment and
entanglement due to the presence of inter-qubit interaction, the
effects of spin-orbit parameter D and temperature difference
parameter ΔT on the entanglement of the system have been
investigated. We show that for a fixed set of the system
parameters, entanglement can be produced just by adjusting the
temperature difference between the reservoirs. The size of this
entanglement, which is induced by temperature difference of
reservoirs, increases as the spin-orbit parameter D increases.
Also we find that, this environment induced entanglement can be
improved if the qubit influenced by the weaker magnetic field is
in contact with the hotter reservoir, i.e. indirect geometry of
connection. In this case, the amount of asymptotic entanglement
increases as D increases. Regardless of the geometry of
connection, increasing D causes the appearance of entanglement
in the larger regions of TM-ΔT plane, therefore
entanglement can exist in higher temperatures and temperature
differences. Furthermore, increasing D enhances the amount of
entanglement in these regions. We also show that the state of the
system can be found in the maximally entangled state for the case
of zero temperature reservoirs and large amount of the spin-orbit
parameter. 相似文献