Interaction of gravitational waves with a superconducting cylindrical antenna

In this paper we investigate the effects of gravitational waves (GW) on a superconducting cylindrical antenna (S-antenna). We suggest that the electric fields induced by GW of dimensionless amplitudeh - 10^–24 in the interior of existing cylindrical antenna might be detectable.     

表面注入P-top区double RESURF功率器件表面电场模型

提出表面注入P-top区double RESURF功率器件表面电场和击穿电压解析模型. 基于分区求解二维Poisson方程, 获得double RESURF表面电场的解析式. 借助此模型, 研究了器件结构参数对表面电场和电势的影响; 计算了漂移区长度和厚度与击穿电压的关系, 给出了获得最大击穿电压和最小导通电阻的途径. 数值结果, 解析结果和试验结果符合较好.     

Optical properties of Dy ions in sodium gadolinium tungstates crystal

Dy³⁺-doped NaGd(WO₄)₂ crystal with sizes of about Φ20×40 mm² was grown by the Czochralski technique along the (0 0 1) orientation. Polarized absorption spectra, fluorescence spectra, and fluorescence decay curve of Dy³⁺-doped NaGd(WO₄)₂ have been recorded at room temperature. Based on the Judd-Ofelt (J-O) theory, the intensity parameters from the measured line strengths were evaluated. The J-O parameters were used to predict radiative transition probabilities, radiative lifetimes and branching ratios for various excited levels of Dy³⁺-doped NaGd(WO₄)₂ crystal. The luminescent quantum efficiency of the ⁴F_9/2 level was determined to be approximately 63% for this material. The emission cross-section of the ⁴F_9/2→⁶H_13/2 transition was estimated by using the Füchtbauer-Ladengurg method.     

Tl系超导薄膜金属涂层的生长与特性研究

我们研究了Tl-2212超导薄膜在带有YSZ/CeO2缓冲层和带有CeO2/YSZ/CeO2缓冲层的Ni金属RABiTS基带上的生长情况.基带上的缓冲层是采用PLD方法制备的,Tl-2212薄膜的制备采用了磁控溅射和后热处理两步方法.XRD 实验结果表明,Tl-2212薄膜都具有很好的C轴垂直于膜面的织构,并具有双向外延生长特性.在CeO2/YSZ/CeO2/Ni基带上制作的Tl-2212薄膜的Tc达到102.8 K,Jc(77 K,0 T)达到2.6 MA/cm2;在YSZ/CeO2/Ni基带上薄膜Tc可达97.7 K,Jc(77 K,0 T)也可以达到0.45 MA/cm2.     

减小球差的环带透镜设计

根据光线经过折射面后像距和折射面参数之间的关系,将折射面划分为若干同心圆环,各圆环之间沿光轴有一定的轴向间隔。一束平行于光轴的光线入射后,经过不同部分光线的像点相互重叠从而使球差减小。根据上述思想用单透镜构造一个透镜称为环带透镜,然后以环数为2的透镜为例用CODE V进行像差分析。和双胶合透镜比较得出:环带透镜的球差、波像差以及轴上点的弥散斑优于胶合透镜,同时光学传递函数指标提高,接近衍射极限。     

Self-organized ZnAl2O4 nanostructures grown on -sapphire

Self-organized ZnAl₂O₄ nanostructures with the appearance (in SEM) of high aspect ratio horizontal nanowires are grown on uncatalysed c-sapphire by vapour phase transport. The nanostructures grow as three equivalent crystallographic variants on c-sapphire. Raman and cathodoluminescence spectroscopy confirm that the nanostructures are not ZnO and TEM shows that they are the cubic spinel, zinc aluminate, ZnAl₂O₄, formed by the reaction of Zn and O with the sapphire substrate.     

Macroscopic quantum coherence in a single molecular magnet and Kondo effect of electron transport

We report a Kondo-effect study of electron transport through a quantum dot with embedded biaxial single-molecule magnet based on slave boson mean-field theory and non-equilibrium Green-function technique. It is found the macroscopic quantum coherence of molecule-magnet results in the Kondo peak split of differential conductance due to interaction between electron and molecular magnet. It is also demonstrated that both the peak height and position can be controlled by the sweeping magnetic field and polarization of ferromagnetic electrodes. The characteristic peak split may be used to identify the macroscopic quantum coherence and develop molecule devices.