Generation of multiple-particle cluster state via cavity QED

This paper proposes schemes for generating multiple-photon and multiple-atom cluster states, respectively. The schemes are based on the cavity input-output process and atomic or photonic states measurement, and the successful probabilities approach unity in the ideal case. The numerical simulations show that the produced multiple-particle cluster states have high fidelity even if the Lamb-Dicke condition is not satisfied. Some practical imperfections, such as atomic spontaneous emission and output coupling inefficiency, only decrease the success probability but exert no influence on the fidelity of generated multiple-particle cluster states. From the experimental point of view, smaller operation number and lack of need for individual addressing keeps the schemes easy to implement. These schemes may offer a promising approach to the generation of a large-scale cluster state.     

Ne、Ar、Kr、Xe等离子体Planck和Rosseland平均不透明度的近似计算

根据平均原子模型和类氢光吸收系数，近似地计算了Ne、Ar、Kr、Xe等惰性元素高温、高密度等离子体的Planck和Rosseland不透明度。在计算线谱吸收过程中，采用了唯象方法处理线谱演化成谱带时的加宽效应及谱带重叠效应。将不透明度数据拟合成温度和密度的幂函数形式，它能够用于辐射体的数值拟合。     

非理想情况下磁化球形重质气体物理爆炸的数值模拟

采用磁流体力学(magnetohydrodynamics, MHD)方程组对非理想情况下磁场对球形重质气体物理爆炸的作用过程进行数值模拟,同时,为了保证每一步中磁场散度为零,引入由12-solve CTU算法衍生出的CTU+CT算法。结果清晰地显示了重质气体团在磁场影响下的整个爆炸过程。在非理想情况下,爆炸过程中气体团界面产生液滴状结构,随着气体团被压缩,不稳定性现象最终得到抑制。从结果中看出,电阻和双极扩散效应会阻碍磁场对气体团的作用,同时,双极扩散效应还会增大磁压力的作用范围。     

Quantum state transfer via adiabatic passage

Based on adiabatic passage, we propose a scheme for implementing the quantum transfer of an unknown atomic state. In our scheme, we utilize photons for ideal quantum transmission between two cavities with the successful probability being about 1. Meanwhile, the scheme is robust against the effects of atomic spontaneous emission. It may be useful for transferring quantum information among spatially distant atoms.     

截锥体头型弹丸低速斜入水实验研究

为研究截锥体头型弹丸在低速斜入水条件下,头部直径大小对入水空泡及弹道特性的影响,基于高速摄像方法,开展不同截锥体头型弹丸低速倾斜入水对比实验,得到了截锥体头弹丸头部直径大小对入水空泡、运动速度、俯仰角的影响规律。实验结果表明:截锥体头弹丸头部直径越大,尾部越早与空泡下壁面发生碰撞;头部直径大小对空泡深闭合时间几乎没有影响;弹丸空泡随头部直径增大而增大;头部直径过大或者过小均不利于入水稳定性;弹丸速度低于临界值时呈上升趋势,高于临界值时将呈现下降趋势。     

缩径焊接空心球压弯下节点刚度研究

以缩径焊接空心球节点为研究对象,运用正交设计法设计了 9个试件,试验研究了压弯受力状态下节点的名义抗弯刚度.利用ABAQUS软件建立缩径焊接空心球节点分析模型,采用线性强化应力-应变关系,考虑几何和材料非线性的影响,对压弯受力状态下的缩径焊接空心球节点的抗弯刚度进行了有限元分析,绘制了节点弯矩-转角曲线,得到了节点名义...     

超曲面上Cauchy-Riemann函数的全纯扩充

本文讨论复空间中实超曲面上CR函数的全纯扩充中,关于极小凸点的判定及刚性超曲面的整体扩充等问题。     

Evolution of global enstrophy in cylinder wake controlled by Lorentz force

The Okubo-Weiss function is correlated with the fluid particle compression, deformation and vorticity, which provides a simple way to characterize different regions of a flow-field. In the present paper, it shows mathematically that the global integration of Okubo-Weiss function is always equal to zero for a two dimensional incompressible flow with no-slip boundaries. To validate the conclusion, a flow passing a circular cylinder con- trolled by the electromagnetic force is calculated numerically as an example. Distributions of global enstrophy, total squared strain and Okubo-Weiss function in the controlled flow field are discussed. The influence of Lorentz force on the distribution is analyzed.     

超声速平面混合层小激波的形成与演变

为了揭示超声速混合层中小激波形成机理及其与涡相互作用的演变过程,本文基于大涡模拟（LES）方法,结合五阶精度混合TCD／WENO格式,对超声速平面混合层在对流马赫数为Mc=0．65条件下的流场结构进行了数值模拟,数值结果详细描述了超声速混合层中小激波的形成过程。研究了小激波形成后,随涡运动而产生的变形、脱落及发展过程。同时,对混合层双涡合并过程中,小激波与相邻涡相互作用所产生的变形与演变过程进行了讨论。     

低对流马赫数平面混合层的声波产生机理

为了详细揭示低对流马赫数下平面混合层的声波产生机理,基于高精度混合格式,对空间发展的平面混合层的流场结构及其声场特性进行了直接模拟.数值结果描述了对流马赫数为0.4时混合层失稳产生的涡串以及涡发展过程中所存在的各种声源,其中包括常规的单涡四极子声源、双涡以及多涡合并过程产生的四极子声源,另外,还发现因K-H不稳定引起混合层振动而产生的偶极子声源,声波以平面波的形式向周围传播.