信号与本振光振幅分布对星间相干光通信系统混频效率的影响

星间相干光通信系统中,信号光与本振光的不同分布将影响外差混频效率.在假设信号光与本振光偏振一致、相位匹配、几何中心重合的前提下,详细推导了信号光振幅为平面波(Uniform)、高斯(Gauss)分布,本振光为艾里斑(Airy)、Uniform及Gauss分布时的6种外差混频效率关系式,其中4种得到了精确的解析式.在此基...     

A relativistic continuum Hartree-Bogoliubov theory description of N=3 isotones

The ground-state properties of N=3 isotones and mirror nuclei have been investigated in the Rrelativistic Continuum Hartree-Bogoliubov theory with the NLSH effective interaction. Pairing correlations are taken into account by a density-dependent δ-force. The calculations show that the proton density distributions of ⁸B and ⁹C have a long tail, the core has an increasing tendency of ⁹C and the paired off valence protons make the halo distribution shrink. The cross sections for the ⁸B(⁹C)+¹²C reaction which are consistent with the experimental data are calculated using the Glauber model. On the whole, we think that ⁸B is a one-proton halo nucleus and ⁹C is a two-proton halo nucleus.     

The feature extraction of ship radiated noise with Fourth Order Cumulant diagonal slice

After analyzed Fourth Order Cumulant (FOC) of harmonic signals theoretically, the FOC is divided into three parts. The first is the cubic frequency (phase) coupling components. The second is the double frequency (phase) coupling components (w1 w2=w3 w4). The last is the rest components. On the basis of the study, the FOC diagonal slice is used to extract the cubic frequency (phase) coupling feature, double frequency (phase) coupling feature and the “sub-band energy“ feature of ship-radiated noise. In terms of the features, the three type ships are classified by artificial neural network. The correct classification rates of A, B and C ships are 92.5%, 92.7%, 88.6%, respectively. The results show the method is effective and practical.     

激光锁相合成技术

本文阐述一种新型激光锁相相干合成方法,着重研究实现这种锁相相干合成的关键技术,即高效率光束耦合问题,提出了几种不同的耦合方法。为获得高的相干合成输出,用计算机优化设计方法计算了不同数目光束耦合时光束问应满足的位相关系及可能达到的合成输出效率。最后,本文讨论了用多元位相光栅代替二元位相光栅进行合成输出的有关问题。     

利用A型原子与光场的纠缠态传送腔场的奇偶相干态的叠加态

根据简并A型三能级原子与单模光场的非共振相互作用系统的改进型有效哈密顿量，利用矩阵方法推导出任意初始情况下原子—光场系统的波函数，通过改变相互作用时间，制备出原子—腔场系统的纠缠态，提出利用原子—腔场系统的纠缠态进行概率传送腔场的奇、偶相干态的叠加态的有效方案，对于振幅很大的单模光场，通过实行Bell态测量，能成功地概率传送腔场的奇偶相干态的叠加态，其成功的总概率为0.25。     

束缚态径向方程和Ξ-超核的结合能

无论从薛定谔方程或是Dirac方程的低能近似出发都可导出同一标准形式的径向方程,这种径向方程可用三点中央差分格式从中心两点出发向外递推求解. 给出了一种求解束缚态的能量本征值及其径向波函数的方法并计算分析了几个Ξ-超核的基态结合能.     

相干态Jaynes—Cummings模型中场的振幅N次方压缩

研究了一初始处于基态的二能级原子与相干态光场相互耦合的单光子Ｊａｙｎｅｓ－Ｃｕｍｍｉｎｇｓ（Ｊ－Ｃ）模型中场的振幅Ｎ次方压缩特性，并讨论了其压缩度随光场的初始平均光子数ｎ和压缩阶数Ｎ的变化。     

单模加光子双模SU(2)相干态的非线性高阶差压缩

本文研究了单模加光子双模SU(2)相干态|M,ζ;m〉=Ama m|M,ζ〉的非线性高阶差压缩(即N次方X压缩)效应.数值计算结果表明:对于单模加光子双模SU(2)相干态,光场存在着非线性高阶差压缩??—N(=1,2,3,4,…)次方X压缩效应,且随着光场总光子数M的增加,N次方X压缩效应增强,但增大场模光子增加数m或增大N次方X压缩的压缩阶数N,N次方X压缩效应减弱.     

SrⅠ 5s~(21)S_0-5s4d~1D_2、5s~(21)S_0-5s6d~1D_2单光子电四极矩E2跃迁及其5s~(21)S_0-5s6d~1D_2单光子电四极矩E2前向相干辐射的研究

用染料激光来激发Ｓｒ原子，首次在实验上发现较强的ＳｒⅠ５ｓ２１Ｓ０５ｓ４ｄ１Ｄ２、５ｓ２１Ｓ０５ｓ６ｄ１Ｄ２单光子电四极矩Ｅ２共振跃迁离化信号，并对５ｓ２１Ｓ０５ｓ６ｄ１Ｄ２共振离化时，伴随出现的前向相干辐射进行了判断与分析。