排序方式: 共有39条查询结果,搜索用时 62 毫秒
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为了得到分辨率更好的平板透镜,对此进行了研究。利用有限元的方法研究了由水/水银材料组合的二维蜂窝结构声子晶体平板透镜的负折射成像特性,通过数值仿真计算了声子晶体的能带结构、等频色散曲线,模拟了点源成像,并且利用高斯波束验证了声子晶体平板透镜的负折射现象,得到了有效折射率neff =-1的成像。对比相同材料的正方晶格和三角晶格而言,该模型的成像效果更佳。为了改善成像分辨率,还在原来的模型上进行了改进,得到了分辨率约为0.37λ的亚波长像。 相似文献
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光脉冲在含玻色元激发的非线性介质中的传播与面积定理 总被引:1,自引:1,他引:0
研究了取决于场与玻色(boson元激发瞬间相互作用的光信号传播问题。导出了相应的‘面积定理’,是将只关系到光脉冲在二能级系统中传播的面积定理的一种推广。所得结果和用光与玻色物质耦合模型对增强吸收型光双稳的解决是一致的。 相似文献
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Impact of incident direction on neutron-induced single-bit and multiple-cell upsets in 14 nm FinFET and 65 nm planar SRAMs 下载免费PDF全文
Shao-Hua Yang 《中国物理 B》2022,31(12):126103-126103
Based on the BL09 terminal of China Spallation Neutron Source (CSNS), single event upset (SEU) cross sections of 14 nm fin field-effect transistor (FinFET) and 65 nm quad data rate (QDR) static random-access memories (SRAMs) are obtained under different incident directions of neutrons: front, back and side. It is found that, for both technology nodes, the "worst direction" corresponds to the case that neutrons traverse package and metallization before reaching the sensitive volume. The SEU cross section under the worst direction is 1.7-4.7 times higher than those under other incident directions. While for multiple-cell upset (MCU) sensitivity, side incidence is the worst direction, with the highest MCU ratio. The largest MCU for the 14 nm FinFET SRAM involves 8 bits. Monte-Carlo simulations are further performed to reveal the characteristics of neutron induced secondary ions and understand the inner mechanisms. 相似文献
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We present the acoustic band gaps (ABGs) for a geometry of three-dimensional complex acoustic crystals: the NaCl-type structure. By using the super cell method based on the plane-wave expansion method (PWE), we study the three configurations formed by water objects (either a sphere of different sizes or a cube) located at the vertices of simple cubic (SC) lattice and surrounded by mercury background. The numerical results show that ABGs larger than the original SC structure for all the three configurations can be obtained by adjusting the length-diameter ratio of adjacent objects but keeping the filling fraction (f = 0.25) of the unit cell unchanged. We also compare our results with that of 3D solid composites and find that the ABGs in liquid composites are insensitive to the shapes as that in the solid composites. We further prove that the decrease of the translation group symmetry is more efficient in creating the ABGs in 3D water-mercury systems. 相似文献
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