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11.
Electronic properties of hydrogen- and oxygen-terminateddiamond surfaces exposed to the air 下载免费PDF全文
The electronic properties of hydrogen- and oxygen-terminated diamond
surfaces exposed to the air are investigated by scanning probe
microscopy (SPM). The results indicate that for the
hydrogen-terminated diamond surface a shallow acceptor above the
valence-band-maximum (VBM) appears in the band gap. However, the
oxygen-terminated diamond film exhibits a high resistivity with a
wide band gap. Based on the density-functional-theory, the densities
of states, corresponding to molecular adsorbate in hydrogenated and
oxygenated diamond (100) surfaces, are studied. The results show
that the shallow acceptor in the band gap for the
hydrogen-terminated diamond film can be attributed to the
interaction between the surface C--H bonding orbitals and the
adsorbate molecules, while for the oxygen-terminated diamond film,
the interaction between the surface C--O bonding orbitals and the
adsorbate molecules can induce occupied states in the valence-band. 相似文献
12.
Frontiers of Physics - This article presents a review of our present understanding of the spin structure of the unpolarized hadron. Particular attention is paid to the quark sector at leading... 相似文献
13.
为确保天线的表面精度和工作性能,综合考虑了天线结构重量、频率、布局等诸多因素,提出了基于优化的设计方法来平衡这些因素.以绳索预张力大小、纵向调整索数目、辐射单元数目为设计变量,结构重量和网状反射面的均方根误差最小为目标函数,应力和频率为约束条件,建立了索网式可展开天线设计的多目标优化数学模型.并将多目标化为单目标用遗传算法进行了求解,结果表明:在结构表面精度达到约2mm 的条件下,结构重量能减轻12%.这表明文中所提出的优化设计方法是有效可行的,对网状天线结构的设计具有一定的指导意义. 相似文献