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采用基于密度泛函理论框架下的第一性原理计算,研究了不同浓度N型掺杂锗的电子结构和光学性质.掺杂元素分别为磷和铋,并对掺杂后的电子态密度和光学性质进行计算、分析.计算结果表明:N型掺杂会使得费米能级向导带方向移动.在低能区段,介电函数、折射率和吸收系数都受到影响,但到高能区后只有消光系数和吸收系数会被影响;反射率在整个能区都受影响,在中能区掺杂会使反射率提高,在低、高能区会减弱反射率;对损失函数的影响是掺杂浓度越高、损耗峰越小、峰值出现处能量越高.研究结果对N型掺杂半导体锗的光学应用具有一定的指导意义,可以根据上述结论有针对性地调节掺杂浓度和能量范围. 相似文献
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伴随着现代信息技术的飞速发展,其在教育教学领域的运用也更加广泛,而SOA技术就是教育教学当中运用最为频繁的一项信息技术.在SOA技术的使用之下,电大逐渐构建起网络教学平台用于突破传统课堂教学的束缚和限制,本文将通过对SOA技术的简要概述进行介绍作为根本出发点,从电大教学平台的设计目标以及数据交换平台的设计两方面阐述基于SOA的电大教学平台设计. 相似文献
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High-Pressure Annealing Effect on Glass Transformation Temperature of Zr41Ti14Cu12.5Ni10Be22.5 Bulk Metallic Glass
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Zr41 Ti14 Cu12.5Ni10Be22.5 bulk metallic glasses (BMG) are annealed at a temperature of 603 K under ambient and high pressures in the range of 3-6 GPa. The effect of high pressure annealing on the nanocrystallization process of compressed specimens is investigated by x-ray diffraction, differential scanning calorimetry and transmission electron microscopy. Experimental results show that the grain size of the crystalline phase decreases with the increasing pressure. For the Zr41Ti14Cu12.5Nil0Be22.5 BMG annealing at 603K in the pressure range of 0- 6 GPa, the activation energy 159.68 kJ/mol and the activation volume △V* =0.94 cm^3/mol are determined. The mechanism for the effects of the high pressure on the nanocrystallization process of the BMG is discussed. 相似文献
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Third-order optical nonlinearity of a novel copper phthalocyanine-ferrocene dyad is measured by femtosecond forward degenerate four-wave mixing (DFWM) technique at 800 nm. The second-order hyperpolarizability of the novel copper phthalocyanine-ferrocene dyad is measured to be 1.74 ×10^-30 esu. This large and ultrafast thirdorder optical nonlinear response is mainly enhanced by the formation of intramolecular charge-transfer which can enhance the delocalized movements of the large π-electrons in the molecules. 相似文献