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121.
A theorem upon refractive index as a function of wavelength is derived starting from the Taylor expansion around the origin of this function. Our result involves the above index, the group index, and the coefficient of material dispersion all extrapolated to zero wavelength. 相似文献
122.
介绍了测量不确定度的评定方法及其在基准试剂纯度、干涉滤光片波长标准物质、锌合金成分标准物质中的应用实例。 相似文献
123.
Different all-optical logic operations, memory blocks etc. are developed using the inherent parallelism of optics. In any digital communication and computation system, the role of serial to parallel and parallel to serial data conversion are very much essential for making a data convenient for transition.Here in this paper, the authors propose a new scheme for developing an all-optical parallel to serial data conversion system by using optical J-K Flip-Flops and some logic gates based on optical non-linear switches. The uses of such switches are widely established in the area of optical parallel computation.This process can be extend for developing some all-optical digital devices like shift register, optical pulse counters etc. The proposed scheme deals with the best use of high parallelism of the optics, so the super-fast processing speed can be achieved. 相似文献
124.
The proposed all-optical 2-D switching networks are (i) M×N-gon prism switches (M2, N3) and (ii) 3-D grids of any geometry N3. For the routing we assume (1) the projection of the spatial architectures onto plane graphs (2) the embedding of the latter guest graphs into (in)complete host hypercubes (N=4) and generally, into N-cube networks (N3) and (3) routing by means of the cube algorithms of the host. By the embedding mainly faulty cubes (synonyms: injured cubes, incomplete cubes) arise which complicate the routing and analysis. The application of N-cube networks (i) extend the hypercube principles to any N3 (ii) increase the number of plane host graphs and (iii) reduce the incompleteness of the host cubes. Several different embeddings of the intersection graphs (IGs) of 2-D switching networks and several different routings are explained for N=4 and 6 by various examples. By the expansion of the grids (enlargement) internal waveguides (WGs) and internal switches are introduced which interact with the switches of the original 3-D grid without increasing the number of stages (NS). The embeddings by expansion apply to interconnection networks whereas dilation-2 embeddings (dilation ≡ distance of the nearest-neighbour nodes of the guest graph at the host) are rather suitable for the emulation of algorithms. Concepts for fault-tolerant routing and algorithm mapping are briefly explained. 相似文献
125.
We developed a flat passband acoustooptic filter. For the passband flattening, cascaded bandpass and notch filters with different mode converter lengths and conversion strengths were used. We attained a flat passband with flatness of less than 1 dB in the 2 nm range using the device with a second- to first-stage mode converter length ratio of 1.2. 相似文献
126.
Kazunari Ozasa Shigeyuki Nemoto Mizuo Maeda Masahiko Hara 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):89
We have found that the photoluminescence (PL) intensity of CdSe/ZnS nanocrystals placed on a thin film of insulator (GaAsOx/GaAs) depends on excitation wavelength through the interference effects of the excitation light. By employing the multi-reflection/interference calculation, the insulator thickness of the underlying non-uniform patterns can be evaluated by the simple observation of CdSe/ZnS PL with a couple of excitation wavelengths. Moreover, the differences observed for the temporal evolution of CdSe/ZnS PL (blue shifts and degradation) among the excitation wavelengths suggest that the photo-induced changes of chemical composition and surface ligands are responsible for blue shifts and degradation, respectively. 相似文献
127.
电子通过wiggler产生的辐射,除了短波辐射在轴线附近也有较强的长波辐射,在与轴线夹 角1/γ处达到最大.推导出wiggler长波辐射公式,理论分析了这种辐射的特点,并且将 理论分析的结果与数值计算的结果进行了比较.对在红外波长范围内电子束通过弯转磁铁和wiggler时产生的辐射强度和光通量作了计算,结果表明wiggler下的辐射强度和光通量均强 于弯转磁铁.比较了弯转磁铁的边沿辐射、波荡器的渡越辐射和wiggler长波辐射,表明wigg ler在红外波长范围辐射的性能最优.
关键词:
wiggler
波荡器
弯转磁铁
长波辐射 相似文献
128.
129.
An 80 nm bandwidth long wavelength erbium-doped fiber amplifier using a seed light injection method is designed.It is shown that when the wavelength of the seed beam varies from 1520 nm to 1570 nm,the gain at 1610 nm increases and reaches maximum near 1553 nm and then decreases.The gain increases with the seed light power.With the seed light ,the long wavelength Erbium-doped fiber amplifier has 80 nm bandwidth (1570~1650 nm),30 dB gain and noise figure less than 5.0 dB. 相似文献
130.
Four-wave mixing in semiconductor laser amplifiers enables various applications in photonic switching including wavelength conversion, space and time switching, optical phase conjugation, and demultiplexing. Switching times faster than 1 ps are possible. 相似文献