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31.
利用离子束溅射技术在ZrO_2衬底上原位制备出YBa_2Cu_3O_(7-δ)高温超导薄膜。薄膜的零电阻温度T_(co)=88K,临界电流密度J_c(77K)=5.2×10~5A/cm~2用X射线衍射和扫描电镜分析了薄膜特性。本文结果表明用离子束溅射法可原位沉积制备出高质量的超导薄膜。  相似文献   
32.
激光输出不稳定性对激光与物质热作用的影响   总被引:2,自引:0,他引:2  
研究了激光与物质相互作用中激光输出不稳定性对材料中温度场颁的影响以及减少这种影响的途径。首次在激光热传导方程中引入噪声项,推导了噪声影响下该激光热传导方程的解。研究发现,温度场的分布受噪声的影响,材料表面温度的涨落较大,而材料的深处涨落较小;温度场的涨落还和激光加热的过程有关,随激光加热时间的增长,温度场的涨落增大。此外,材料的热传导系数、热扩散率和发射率均对温度场的涨落有影响。文中还提出了减小激  相似文献   
33.
The temperature fluctuation of the stainless steel irradiated by a CW CO2 laser is studied. In the experiment, the temperature fluctuation and the temperature rise is measured by the infrared thermal imagers. It is found that the maximum amplitude of the temperature fluctuation is kept constant with the increase of the laser heating time;this is different from aluminum, low carbon steel, epoxylite and polymethylmethacrylate. This characteristic of the stainless steel is determined by the variance of thermal conductivity and thermal diffusivity with the increase of temperature. A thorough study of the effects of the material thermal properties on the temperature fluctuation is needed.  相似文献   
34.
For the NLS+ equation under nonvanishing boundary condition, to avoid complexity due to Riemann surface, required for double-valued function of the usual spectral parameter, starting from a particular auxiliary spectral parameter, a special inverse scattering method is systematically developed, and explicit expressions of the general multi-soliton solutions are successfully obtained. Asymptotic behaviors of the muiti-soliton solutions, additional displacement of center and additional phase shift of the peak are derived. When the boundary value approaches zero, all the formulas become the known ones naturally.  相似文献   
35.
用千瓦级连续CO_2激光作光源,得到复合型砷化镓材料的三阶非线性系数为8.3×10~(-7)esu,同时根据这种材料的杂质能级对其三阶非线性系数进行计算,所得结果与实验相符。  相似文献   
36.
In this paper, based on Maxwell's equations and boundary continuity condi-tions of electromagnetic fields, we derive rigorous vector coupled-wave equations of two-dimensional diffractive patterns for an arbitrary polarization in the resonance domain, and describe the solution to these equations. We verify this theory with a practical example, and show the effectiveness of this method for the resonance-domain diffractive optics.  相似文献   
37.
本文介绍了一种新型的线性扫描光学系统,它由一对处于望远型结构的微透镜阵列和一个普通的会聚透镜组成。微透镜阵列采用二元光学技术进行设计和制作。该装置具有扫描灵敏度高(~1000)、扫描范围大(±100mm)、结构紧凑、价格低廉等优点。  相似文献   
38.
对XeCl准分子激光蒸发YBa_2Cu_3O_(7-x)陶瓷靶产生的等离子体进行了实验和理论研究.利用发射光谱,分辨出等离子体内的各种粒子.并对各种粒子进行了飞行时间谱测量.在实验的基础上,建立了一个等离子体的膨胀模型.计算结果与实验符合较好.  相似文献   
39.
For the NLS+ equation under nonvanishing boundary condition, to avoid complexity due to Riemann surface, required for double-valued function of the usual spectral parameter, starting from a particular auxiliary spectral parameter, a special inverse scattering method is systematically developed, and explicit expressions of the general multi-soliton solutions are successfully obtained. Asymptotic behaviors of the muiti-soliton solutions, additional displacement of center and additional phase shift of the peak are derived. When the boundary value approaches zero, all the formulas become the known ones naturally.  相似文献   
40.
采用简化的综合设计方法,对偶数大点阵位相计算全息光栅进行了优化设计和分析,实验上研制出用于光互连模块的64×64大点阵位相计算全息光栅分束器,优化设计一维衍射效率为80.1%,光强不均匀性小于0.3%。  相似文献   
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