Kerr介质和原子间相互作用对双光子T-C模型中原子偶极压缩的影响

研究了存在Kerr介质时，耦合双原子与单模光场双光子跃迁相互作用系统原子偶极压缩的时间演化规律，讨论了Kerr介质与光场的耦合强度和原子间偶极一偶极相互作用对原子偶极压缩的影响．     

Kerr介质中光场与耦合双原子相互作用系统的光场压缩

研究了存在Kerr介质时，双模光场与耦合二能级原子相互作用系统中光场的压缩性质，讨论了Kerr介质与双模光场的耦合强度χ、初始平均光子数no和原子的初态对光场压缩特性的影响．     

Kerr介质中耦合双原子与压缩真空场Raman相互作用系统中原子的量子特性

研究了存在Kerr介质时，耦合双原子与单模压缩真空场Raman相互作用系统中原子的量子特性，讨论了Kerr介质与光场的耦合强度对耦合双原子与单模压缩真空场Raman相互作用系统中原子的量子特性的影响．     

克尔介质中光场与耦合双原子相互作用系统原子布居数的时间演化特性

研究了存在克尔介质时，双模光场与耦合二能级原子相互作用系统粒子布居数的时间演化规律，讨论了克尔介质与双模光场的耦合强度χ、初始平均光子数no和原子的初态对粒子布居数时间演化的影响。     

光子晶体光纤的研究进展

在14篇文献的基础上，综述了光子晶体新型介质材料的能带结构、带隙产生、制备方法，对光子晶体光纤的制备技术与应用以及新的实验和理论进展作了重点介绍，对其发展前景进行了展望。     

光场与V型三能级原子依赖强度耦合相互作用系统的原子布居的时间演化

利用全量子理论,研究了单模光场与V型三能级原子依赖强度耦合的相互作用系统中原子布居的时间演化特性.采用数值计算的方法讨论了初始场平均光子数和失谐量与原子布居的时间演化关系.     

NdFeB 永磁合金的晶粒相互作用及其对磁体硬磁性能的影响

综述了ＮｄＦｅＢ永磁材料中晶粒间的两种相互作用：长程静磁（偶极）相互作用和近邻晶粒的交换耦合作用,及它们对磁体的硬磁性能的影响;还介绍了研究这些相互作用的两种方法：理论模型计算和实验退磁曲线分析。最后介绍了纳米双相复合永磁材料中的晶粒交换耦合相互作用与材料硬磁性能的关系。     

NdFeB永磁合金的晶粒相互作用及其对磁体磁磁性能的影响

综述了ＮｄＦｅＢ永磁材料中晶粒间的两种相互作用;长程静磁（偶极）相互作用和近邻晶粒的交换耦合作用,及它们对磁体的硬磁性能的影响;还介绍了研究这些相互作用的两种方法;模型计算和实验退磁曲线分析,最后介绍了纳米双相复合永磁材料中的晶粒交换耦合相互作用与材料硬磁性能的关系。     

基于Kerr电光效应的冲击电压下液体电介质空间电荷高速CCD测量

空间电荷的存在直接影响液体电介质的绝缘击穿性能,为了更好地研究空间电荷的动态变化过程,建立了基于Kerr电光效应的冲击电压下液体电介质空间电荷的高速电荷耦合器件(CCD)测量系统。运用高精度光电传感器的测量方法,得到了室温下液体碳酸丙烯酯的Kerr常数。进而通过高速CCD的动态光电测量,并结合图像处理技术,求取了冲击电压下平行板铜电极间电场和空间电荷的动态分布曲线。实验研究表明:在平行板铜电极间,当液体介质中电场达到一定程度时会出现空间电荷的注入与输运,使得极间电场呈现出中间高两边低的分布情况。另外还分析了空间电荷的分布和输运对液体绝缘特性的影响,该研究为分析冲击电压作用下液体介质中空间电荷的产生机制及空间电荷对流注放电的影响奠定了基础。     

Ka波段平板光子晶体波导传输特性测量

为了测量在Ka波段下空气孔型平板光子晶体波导的传输特性,提出采用从金属矩形波导将电磁波耦合进光子晶体波导并测量其传输特性的测试方案。根据两种波导传输模式的场分布,用两段介质尖劈作为电磁波从矩形波导到三角形晶格平板光子晶体波导的模式转换结构,该结构使用电磁场仿真软件找出最优结构尺寸。实验使用聚合物聚醚酰亚胺（PEI）作为介质材料,加工出实际结构,采用AV3629网络适量分析仪测试整个系统的S参数;结果在27~40 GHz之间的传输系数为？7 dB左右,将测试数据与数值结果相比较,并重新设置PEI材料的损耗参数进行仿真,最终,测试结果在损耗角正切为5×10？4的情况下与仿真数据相一致,表明本文提出的模式转换结构有效,平板型光子晶体结构在微波波段的应用打下基础。     

光子运动的蒙特卡罗方法用于LED灯具设计

采用了蒙特卡罗追迹LED灯光子运动,首先构造LED灯光源模型,确定光子运动方向,在光源点至LED灯曲面点之间计算光子频率衰减性,接着分析光子与封装曲面发生弹性散射相函数,材料线性吸收系数,双光子间吸收系数,三光子间吸收系数对光子碰撞的影响,在光子新运动方向确定后对其权重更新,同时大量的光子采用线性同余法产生,最后蒙特卡罗统计光子运动的误差。仿真实验给出了各种光子运动模拟结果,直观地反映了光子特性,为进一步研究复杂的LED灯提供了理论依据。     

基于植物电位波动的极低频脉冲电场对绿豆幼苗生长的影响

为了解决电场生物学效应重复性不好的问题,研究了极低频脉冲电场的生物学效应。结果发现,强度为100kV/m、频率为0.2Hz的极低频脉冲电场处理明显促进了萌发绿豆的芽长和根长生长。对绿豆幼苗超弱光子辐射的研究表明,在绿豆幼苗生长过程中自发发光呈现阶跃式增长,延迟发光积分强度逐渐升高,脉冲电场作用使得自发发光和延迟发光积分强度都有明显的提高,表明极低频脉冲电场促进了绿豆幼苗生长过程中的DNA合成反应和代谢强度,脉冲电场与植物自身电位波动的耦合共振可能是上述极低频脉冲电场生物学效应的成因。     

Single‐photon quantum filtering with multiple measurements

The single‐photon quantum filtering problems have been investigated recently with applications in quantum computing. In practice, the detector responds with a quantum efficiency of less than unity since there exists some mode mismatch between the detector and the system and the single‐photon signal may be corrupted by quantum white noise. Consequently, quantum filters based on multiple measurements are designed in this paper to improve estimation performance. More specifically, the filtering equations for a 2‐level quantum system driven by a single‐photon input state and under multiple measurements are presented in this paper. Four scenarios, ie, (1) 2 diffusive measurements with Q‐P quadrature form, (2) 2 diffusive measurements with Q‐Q quadrature form, (3) diffusive plus Poissonian measurements, and (4) 2 Poissonian measurements, are considered. It is natural to compare the filtering results, ie, measuring a single channel or both channels, which one is better? By the simulation where we use a single photon to excite an atom, it seems that multiple measurements enable us to excite the atom with higher probability than only measuring a single channel. In addition, a measurement back‐action phenomenon is revealed by the simulation results.     

Measurement of the space charge field in transformer oil using itsKerr effect

Nonuniform electric fields >80 kV/cm, have been measured via a relative optical intensity measurement by exploiting the Kerr effect in transformer oil. Transformer oil was used as a Kerr medium in these measurements. Neither a knowledge of the Kerr coefficient nor the actual value of maximum transmitted intensity are required to obtain the absolute value of the electric fields. Electric fields were measured with ac and dc excitations. Space charges resulting from charge injection have been found in transformer oil at room temperature under electric stresses >150 kV/cm with ac excitation and 90 kV/cm under dc excitation. The magnitudes of space charges in transformer oil with ac applied voltages varied from 2 to 50 nC/cm³. The magnitudes of space charges with dc excitation varied from 60 pC/cm³ to 10 nC/cm³. The results illustrate the limitations of the electro-optic technique for investigations of the interfacial electric fields (gas-solid) with transformer oil as the Kerr medium     

Finite element based Kerr electro-optic reconstruction of spacecharge

Recently we used the onion peeling method to reconstruct the axisymmetric electric field distribution of point/plane electrodes from Kerr electro-optic measurements. The method accurately reconstructed the electric field from numerically generated data. However in the presence of experimental noise the performance was less satisfactory. The measurements were especially noisy and unstable near the needle tip which is also the interesting region since most charge injection initiates here. We develop a new algorithm for Kerr electro-optic reconstruction of space charge in axisymmetric point/plane electrode geometries. The algorithm is built on the finite element method (FEM) for Poisson's equation and will be called finite element based Kerr electro-optic reconstruction (FEBKER) hereafter. FEBKER calculates the space charge density directly to avoid the numerical problems associated with taking the divergence of the electric field, uses single parameter light intensity measurements to enable transient analysis, which otherwise is difficult since multiple parameter intensity measurements are slow due to the rotation of polarizers, and is capable of reconstruction even when the number and/or position of measurements are limited by the electrodes and/or the experimental setup. The performance of the algorithm is tested on synthetic Kerr electro-optic data obtained for an axisymmetric point/plane electrode geometry in transformer oil with specified space charge density distributions. The impact of experimental error is analyzed by incorporating random error to the synthetic data. Regularization techniques that decrease the impact of experimental error are applied. In principle FEBKER is applicable to arbitrary three-dimensional geometries as well     

基于Kerr电光效应的变压器油中直流电场测量系统

在直流电场下油纸绝缘系统中,空间电荷的存在会对系统的绝缘性能造成影响。通过实时测量得到绝缘系统中的电场分布和电荷分布具有重要意义。Kerr电光效应法因不会对绝缘系统中电场分布造成影响而得到很多研究者的关注。由于实验系统中包含较复杂的光学器件及微弱信号检测单元,其实现具有一定的难度。文章采用光电二极管作为光接收器件,采用一种交流电压调制方法,结合锁相放大器实现了对微弱信号的检测;通过检测输出光强中直流和所施加的交流信号分量,计算得到了待测直流电场的数值。试验结果表明该系统具有较好的线性度。     

导线接头不同故障类型的紫外成像检测

导线接头在电网中起着机械和电气的连接作用,运行过程中由于导线接头松动、脱落等故障严重威胁电网安全可靠运行,并导致能量损耗,利用合理的手段检测导线接头运行状况一直是运行部门关注的焦点。该文模拟导线接头螺帽松动、螺杆松动、螺栓错位、扭力弯曲和剪切断股这几种典型故障缺陷,利用紫外检测仪检测其作用电压下紫外放电光子数差异。试验结果表明：随着作用电压的提高,导线接头各种故障下的紫外放电光子数随之增加;运行电压下,导线接头各种典型故障下测得的紫外光子数存在明显差异,利用紫外成像检测可以有效用于导线接头的故障检测。研究结果为输电线路的运行状态检测提供了参考。