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851.
P. Pakhlov 《中国物理 C》2008,32(6)
We present a search for new charmonium like states in e~ e~- annihilation using the initial-state radiation and the process e~ e~-→J/ψD~(*)~(*).The analyses are based on a huge data sample recorded near theγ(4S)resonance with the Belle detector at the KEKB e~ e~- asymmetric-energy collider. 相似文献
852.
We provide a method for constructing a set of four-photon states suitable for quantum communication applications. Among these
states is a set of concatenated quantum code states that span a decoherence-free subspace that is robust under collective-local
as well as global dephasing noise. This method requires only the use of spontaneous parametric down-conversion, quantum state
post-selection, and linear optics. In particular, we show how this method can be used to produce all sixteen elements of the
second-order Bell gem
, which includes these codes states and is an orthonormal basis for the Hilbert space of four qubits composed entirely of
states that are fully entangled under the four-tangle measure. 相似文献
853.
For the first time we introduce an operator Δ
h
(γ,ε;κ) for studying Husimi distribution function in phase space (γ,ε) for electron’s states in uniform magnetic field, where κ is the Gaussian spatial width parameter. The marginal distributions of the Husimi function are Gaussian-broadened version
of the Wigner marginal distributions. Using the Wigner operator in the entangled state 〈λ
| representation we find that Δ
h
(γ,ε;κ) is just a pure squeezed coherent state density operator |
γ,ε〉
κ
κ
〈γ,ε
|, which brings much convenience for studying Husimi distribution, so we name Δ
h
(γ,ε;κ) the Husimi operator. We then derive Husimi operator’s normally ordered form that provides us with an operator version to
examine various properties of the Husimi distribution.
Work supported by the National Natural Science Foundation under the grant: 10775097. 相似文献
854.
对数饱和非线性介质中的自洽多模高斯孤子解 总被引:1,自引:1,他引:0
通过解对数饱和非线性介质中光场满足的非线性薛定谔方程,得到一组厄米-高斯型的自洽多模解.在借鉴了R.G.Glauber的相干态理论的基础上,合理假设这组解在非线性介质中呈泊松分布,进而得到了在对数饱和非线性介质中存在高斯孤子的结论,并获得高斯孤子解、非线性系数与泊松参量三者之间的关系.该关系说明,若在介质中存在高斯孤子解,其非线性系数必须满足条件a≥1.当α=1,在介质中仅存在单模高斯孤子,其光斑尺寸必须满足的条件W=1/k n0/n2.在该条件下,以"束腰"注入介质中的高斯光束才可以在保持其光斑尺寸不变的情况下传输,否则光斑尺寸会存在一定的振荡.而振荡方式、振荡范围(表示光斑尺寸展宽或压缩及大小)与输入光束光斑尺寸及其一次导数有直接关系. 相似文献
855.
The major contributions of Richard H. Dalitz to hypernuclear physics, since his first paper in 1955 to his last one in 2005 covering a span of 50 years during which he founded and led the theoretical study of hypernuclei, are reviewed from a personal perspective. Topical remarks on the search for quasi-bound -nuclear states and on kaon condensation are made. 相似文献
856.
Jií Mare 《Nuclear Physics A》2008,804(1-4):296
Self-consistent calculations of single -nuclear states and multi -nuclear states are briefly reviewed. Dynamical effects for deeply bound nuclear states are studied within the relativistic mean-field (RMF) approach. By varying the strength of -nucleus interaction, we cover a wide range of binding energies . Our calculations provide a lower limit on the widths of nuclear bound states for binding energy in the range . Substantial polarization is found in light nuclei for deeply bound nuclear states, with central nuclear densities about twice higher than for the corresponding nuclei without . Multi- nuclear calculations indicate that the binding energy per meson saturates upon increasing the number of mesons embedded in the nuclear medium. The nuclear and densities increase only moderately and are close to saturation, with no indication of any kaon-condensation precursor phenomena. 相似文献
857.
The density of donor impurity states in a square GaAs–AlGaAs quantum well under an intense laser field is calculated taking into account the laser dressing effects on both the Coulomb potential and the confining potential. Using the effective-mass approximation within a variational scheme, the donor binding energy is obtained as a function of the laser dressing parameter, and the impurity position. Our results point out that a proper consideration of the density of impurity states may be of relevance in the interpretation of the optical phenomena related to shallow impurities in quantum wells, where the effects of an intense laser field compete with the quantum confinement. 相似文献
858.
在标量势和矢量势相等的条件下,严格求解了在广义非对称Hartmann势场中粒子运动的Klein Gordon方程;并利用束缚态边界条件,获得了束缚态能谱表达式和由超几何函数表示出的波函数. 相似文献
859.
与二项式光场相互作用的运动原子熵压缩 总被引:2,自引:2,他引:0
运用量子信息熵理论,研究了二项式光场与运动二能级原子相互作用过程中运动原子的信息熵压缩。讨论了不同的原子初态和场的有关参数对原子信息熵压缩的影响。结果表明:选择原子初态、场模结构、场调节参数及原子运动速度可以调控原子信息熵的压缩方向、偶极矩分量值和压缩周期;适当的选择参数可得到持续性的原子信息熵压缩。 相似文献
860.
利用隶玻色子平均场近似理论,并借助于单杂质的Anderson模型的哈密顿量,研究了T型耦合双量子点嵌入正常电极的基态输运性质.结果表明:在体系处于平衡状态时,随着双量子点的耦合强度增加,体系的Kondo 效应被削弱. 当耦合强度足够强时,Kondo量子点态密度的Kondo共振单峰分裂成两个不对等的Kondo共振双峰.在体系处于非平衡状态时,增加两电极的偏压,态密度的Kondo分裂的非对等性明显加强.
关键词:
Kondo效应
态密度
格林函数法
耦合双量子点 相似文献