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1.
Preparation and control of entangled states in the two-mode coherent fields interacting with a moving atom via two-photon process 下载免费PDF全文
We investigate the preparation and the control of entangled
states in a system with the two-mode coherent fields interacting
with a moving two-level atom via the two-photon transition. We
discuss entanglement properties between the two-mode coherent
fields and a moving two-level atom by using the quantum reduced
entropy, and those between the two-mode coherent fields by using
the quantum relative entropy. In addition, we examine the
influences of the atomic motion and field-mode structure
parameter $p$ on the quantum entanglement of the system. Our
results show that the period and the duration of the prepared
maximal atom-field entangled states and the frequency of maximal
two-mode field entangled states can be controlled, and that a
sustained entangled state of the two-mode field, which is
independent of atomic motion and the evolution time, can be
obtained, by choosing appropriately the parameters of atomic
motion, field-mode structure, initial state and interaction time
of the system. 相似文献
2.
双模纠缠相干光场控制下双光子过程中有效二能级原子的信息熵压缩 总被引:1,自引:1,他引:0
根据量子信息理论,研究了与双模纠缠相干场相互作用双光子过程中有效二能级原子的信息熵压缩.讨论了场的初态对信息熵压缩的因影响,并且比较了分别从基于信息熵测不准关系和海森堡测不准关系出发得出的结果.结果表明:信息熵压缩的稳定周期性、压缩方向分别由场的平均光子数和方向角控制,场的纠缠度对信息熵压缩不产生影响.信息熵压缩实现了对原子压缩效应的高灵敏量度. 相似文献
3.
Single-atom entropy squeezing and quantum entanglement in Tavis--Cummings model with atomic motion 下载免费PDF全文
We examine the single-atom entropy squeezing and the atom-field entanglement in a system of two moving twolevel atoms interacting with a single-mode coherent field in a lossless resonant cavity.Our numerical calculations indicate that the squeezing period,the squeezing time and the maximal squeezing can be controlled by appropriately choosing the atomic motion and the field-mode structure.The atomic motion leads to a periodical time evolution of entanglement between the two-atom and the field.Moreover,there exists corresponding relation between the time evolution properties of the atomic entropy squeezing and that of the entanglement between the two atoms and the field. 相似文献
4.
Preparation and control of atomic optimal entropy squeezing states for a moving two-level atom under control of the two-mode squeezing vacuum fields 下载免费PDF全文
From the viewpoint of quantum information,this paper studies preparation and control of atomic optimal entropy squeezing states(AOESS) for a moving two-level atom under control of the two-mode squeezing vacuum fields.Necessary conditions of preparation of the AOESS are analysed,and numerical verification of the AOESS is finished.It shows that the AOESS can be prepared by controlling the time of the atom interaction with the field,cutting the entanglement between the atom and field,and adjusting squeezing factor of the field.An atomic optimal entropy squeezing sudden generation in different components can alternately be realized by controlling the field-mode structure parameter. 相似文献
5.
根据量子信息理论,研究了与双模纠缠相干场相互作用双光子过程中有效二能级原子的信息熵压缩。讨论了场的初态对信息熵压缩的因影响,并且比较了分别从基于信息熵测不准关系和海森堡测不准关系出发得出的结果。结果表明:信息熵压缩的稳定周期性、压缩方向分别由场的平均光子数和方向角控制. 在强场条件下, 场的纠缠度对信息熵压缩不产生影响。当原子反转为零时,基于海森堡测不准关系的方差压缩定义不再有效, 而信息熵压缩实现了对原子压缩效应的高灵敏量度. 相似文献
6.
7.
Considering a two-level atom interacting with the competing two-mode field, this paper investigates the entanglement between the two-level atom and the two-mode field by using the quantum reduced entropy, and that between the two-mode field by using the quantum relative entropy of entanglement. It shows that the two kinds of entanglement are dependent on the relative coupling strength of atom-field and the atomic distribution, and exhibit the periodical evolution. The maximal atom-field entanglement state can be prepared via the appropriate selection of system parameters and interaction time. 相似文献
8.
Entangled states in the two-mode coherent fields interacting with a two-level atom 总被引:2,自引:0,他引:2 下载免费PDF全文
We investigate the entanglement properties of the two-mode coherent fields interacting with a two-level atom via the two-photon transition. We discuss the quantum entanglement between the two-mode coherent fields and the two-level atom by using the quantum reduced entropy and that between the two-mode coherent fields by using the quantum relative entropy. We also examine the influences of the initial states of the atom and the two-mode coherent fields on the quantum entanglement of the system. Our results show that three types of entangled states can be prepared via the two-mode coherent fields interacting with a two-level atom and choosing appropriately the initial-state parameters of the system. 相似文献
9.
Entropy squeezing for a two-level atom in two-mode Raman coupled model with intrinsic decoherence 总被引:1,自引:0,他引:1 下载免费PDF全文
In this paper, we investigate the entropy squeezing for a two-level
atom interacting with two quantized fields through Raman coupling.
We obtain the dynamical evolution of the total system under the
influence of intrinsic decoherence when the two quantized fields are
prepared in a two-mode squeezing vacuum state initially. The effects
of the field squeezing factor, the two-level atomic transition
frequency, the second field frequency and the intrinsic decoherence
on the entropy squeezing are discussed. Without intrinsic
decoherence, the increase of field squeezing factor can break the
entropy squeezing. The two-level atomic transition frequency changes
only the period of oscillation but not the strength of entropy
squeezing. The influence of the second field frequency is
complicated. With the intrinsic decoherence taken into
consideration, the results show that the stronger the intrinsic
decoherence is, the more quickly the entropy squeezing will
disappear. The increase of the atomic transition frequency can
hasten the disappearance of entropy squeezing. 相似文献
10.
Optimal entropy squeezing sudden generation and its control for an effective two-level moving atom entanglement with the two-mode coherent fields 下载免费PDF全文
From the viewpoint of quantum information, this paper proposes a
concept and a definition of the atomic optimal entropy squeezing
sudden generation (AOESSG) for the system of an effective two-level
moving atom which entangles with the two-mode coherent fields. It
also researches the relationship between the AOESSG and
entanglement sudden death of the atom-fields, and discusses the
influences of atomic initial state on the AOESSG and obtains the
system parameter which controls the AOESSG. 相似文献
11.
LIUXiao-Juan FANGMao-Fa 《理论物理通讯》2004,42(1):103-109
From a quantum information point of view we investigate the entropy squeezing properties for a two-level atom interacting with the two-mode coherent fields via the two-photon transition. We discuss the influences of the initial state of the system on the atomic information entropy squeezing. Our results show that the squeezed component number, squeezed direction, and time of the information entropy squeezing can be controlled by choosing atomic distribution angle, the relative phase between the atom and the two-mode field, and the difference of the average photon number of the two field modes, respectively. Quantum information entropy is a remarkable precision measure for the atomic squeezing. 相似文献
12.
通过求解系统的Milburn方程,研究了两能级原子与双模SU(1,1)相干态光场发生相互作用系统中,原子与场的纠缠及双模SU(1,1)相干态场的模间纠缠随时间的演化问题,讨论了内禀退相干、双模光子数差等对纠缠度的影响.结果表明,存在内禀退相干时,随着时间的演化,场-原子纠缠逐渐减小到一个确定值,而模间纠缠逐渐增大到一个确定值,两者演化的最终值只取决于双模光子数差和平均光子数,而与内禀退相干因子无关.
关键词:
Milburn理论
SU(1
1)相干态
量子约化熵
量子相对熵 相似文献
13.
LIU Xiao-Juan FANG Mao-Fa 《理论物理通讯》2004,42(7)
From a quantum information point of view we investigate the entropy squeezing properties for a two-level atom interacting with the two-mode coherent fields via the two-photon transition. We discuss the influences of the initial state of the system on the atomic information entropy squeezing. Our results show that the squeezed component number,squeezed direction, and time of the information entropy squeezing can be controlled by choosing atomic distribution angle,the relative phase between the atom and the two-mode field, and the difference of the average photon number of the two field modes, respectively. Quantum information entropy is a remarkable precision measure for the atomic squeezing. 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
15.
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
16.
17.
运用全量子理论并结合数值计算方法,研究了Kerr介质腔中处于Bell态的两个全同二能级纠缠原子与双模纠缠相干光场相互作用系统的原子偶极压缩特性.讨论了双原子体系的初态、光场的平均光子数、双模纠缠相干光场的纠缠程度以及Kerr介质与双模光场的耦合强度对原子偶极压缩特性的影响.结果表明:双原子体系的初态为|β11>时,不会出现偶极压缩效应;初态为|β00>,|β01>或|β10>时在一定条件下可能出现原子压缩效应,且此时原子压缩的特性与Kerr介质与双模光场的耦合强度、初始光场的平均光子数、双模纠缠相干光场的纠缠程度有关.
关键词:
量子光学
Bell态
双模纠缠相干光场
Kerr介质 相似文献
18.
邹艳 《原子与分子物理学报》2009,26(1):138-144
运用全量子理论研究了初始处于Bell态(对称迭加态或反对称态)的两原子与双模纠缠相干光场相互作用系统中场熵的演化特性. 分析了光场强度、光场纠缠度及原子间相互作用强度对场熵演化特性的影响. 结果表明:原子初态处于反对称态时,场熵始终为零;原子初态处在对称迭加态时,增大光场强度场熵的时间演化曲线逐渐变成较规则的振荡曲线,原子间的相互作用强度对双原子间纠缠度有显著的非线性调制作用. 相似文献
19.
邹艳 《原子与分子物理学报》2008,25(5)
运用全量子理论研究了初始处于Bell态(对称迭加态或反对称态)的两原子与双模纠缠相干光场相互作用系统中场熵的演化特性. 分析了光场强度、光场纠缠度及原子间相互作用强度对场熵演化特性的影响. 结果表明:原子初态处于反对称态时,场熵始终为零;原子初态处在对称迭加态时,增大光场强度场熵的时间演化曲线逐渐变成较规则的振荡曲线,原子间的相互作用强度对双原子间纠缠度有显著的非线性调制作用. 相似文献
20.
We have investigated the evolution of the atomic quantum entropy and the entanglement of atom-photon in the system with competing k-photon and l-photon transitions by means of fully quantum theory, and examined the effects of competing photon numbers (k and l), the relative coupling strength between the atom and the two-mode field (A/g), and the initial photon number of the field on the atomic quantum entropy and the entanglement of atom-photon. The results show that the multiphoton competing transitions or the large relative coupling strength can lead to the strong entanglement between atoms and photons. The maximal atom-photon entanglement can be prepared via the appropriate selection of system parameters and interaction time. 相似文献