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51.
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F. C. Peiris M. R. Buckley O. Maksimov M. Munoz M. C. Tamargo 《Journal of Electronic Materials》2003,32(7):742-746
We have used a combination of prism-coupling, reflectivity, and ellipsometric techniques to investigate the indices of refraction,
n, of a series of BexZn1−xTe thin films grown on InP substrates. After determining the concentrations of each of the BexZn1−xTe alloys using x-ray diffraction measurements, we measured their n at discrete wavelengths using a prism-coupler setup. In
addition, we used reflectivity measurements to complement the prism-coupler data and arrive at the dispersion relations of
n for the BexZn1−xTe alloys below their fundamental energy gaps. We then employed a rotating analyzer-spectroscopic ellipsometer to measure
the complex reflection ratio for each of the films at angles of incidence of 65°, 70°, and 75°. By using the n values obtained
from both the prism-coupler and the reflection-spectroscopy techniques to guide the ellipsometric analysis, we were able to
obtain accurate results for the dispersion of n for the BexZn1−xTe alloys, not only below their fundamental energy gaps, but also above their energy gaps (up to 6.5 eV) using these three
complementary techniques. 相似文献
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高透射比紫外偏光棱镜 总被引:2,自引:1,他引:1
报导一种由方解石和氟化钙晶体制成的棱镜在紫外区有非常高的透射比。通过精挑方解石,透射范围可到达0.21μm。 相似文献
55.
本文以格兰·泰勒棱镜为例,给出了任意入射面上的视场角计算公式,分析了视场角与入射面方位的关系,为高精度棱镜的测量和棱镜特征参量的精确标定提供了依据。 相似文献
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本文介绍了道路灯具反射器的演变及现状,提出了一种可分布矩形光束的多棱镜面反射器道路灯具的设计原理,并分析其照明质量及低杆安装的可行性,展望了它在道路照明中的应用前景。 相似文献
59.
In the Kumano forearc basin, offshore SW Japan, the potential occurrence of hydrocarbons has been inferred from both geophysical surveys which point to the presence of natural gas hydrates, and geochemical analyses of gas samples recovered from boreholes and submarine mud volcanoes. The forearc basin is located in the inner part of the Nankai Trough where the Philippine Sea plate is subducting northwards beneath SW Japan. The basin succession unconformably overlies a deformed accretionary prism complex. Hydrocarbons with both microbial and thermogenic origins have been recorded in the Kumano Basin, but the thermogenic petroleum potential is poorly constrained because the regional‐scale geological architecture of the Nankai subduction zone is not well understood. In this paper, the regional‐scale petroleum potential of the Nankai Trough is investigated based on the geological interpretation of new seismic reflection images. The images were derived from legacy seismic survey data using advanced processing techniques such as reverse time migration, which make use of both primary and multiple reflections in wide‐angle seismic data collected with ocean‐bottom seismographs. In the study area, a seaward‐dipping reflector was identified which terminates at the plate boundary décollement and which is interpreted as part of the boundary between previously‐identified older (>14 Ma) and younger (<6 Ma) accretionary prisms. A triangle body at the base of the younger accretionary prism is interpreted to consist of underthrusted sediments including thick hemipelagic mudstones with source rock potential which were scraped off the down‐going oceanic plate. These tentatively identified, deeply‐buried mudstones may have the potential to generate thermogenic hydrocarbons which may then migrate upwards along dipping carrier beds or faults and fractures to the unconformity at the base of the Kumano forearc basin succession. The presence of hydrocarbons in the accretionary prism may be inferred from positive amplitude anomalies which have been identified in the reprocessed multi‐channel seismic data. The new reflection interpretations therefore allow the potential for thermogenic petroleum to be proposed in the study area. The hydrocarbon potential at this subduction margin may therefore rely not only on shallow microbial methane, but may also involve deeper, thermogenic petroleum generated within the underlying accretionary prism. 相似文献
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