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41.
综述介质光波导中模式分析方法的最新进展。着重分析严格的数值分析方法及近似方法最近的研究进展。依据方法的计算精确度、计算效率和计算复杂度等因素.对有限元法和有限差分法这两种数值分析方法以及有效指数法和频谱指数法等近似方法进行讨论。论述磁光波导的分析方法。  相似文献   
42.
Formulas for calculating the spectral characteristics of waveguide arrays, which are incorporated into waveguide spectrum analyzers based on planar waveguides, channel waveguides, and fiber optical waveguides, are derived taking into account the contribution of both the waveguide dispersion and the material dispersion to the dispersion factor. These formulas are used to study the dependence of the dispersion factor on the waveguide-system parameters for specific models of waveguide arrays. It is shown that consideration of contributions of the waveguide dispersion and material dispersion can affect profoundly the spectral characteristics of waveguide arrays.  相似文献   
43.
We studied the growth of nanocrystalline silicon (nc-Si) thin film exhibiting a strong room temperature photoluminescence (PL) at 1.81–2.003 eV. The amorphous silicon was crystallized by Ni silicide mediated crystallization (Ni SMC) and then Secco-etched to exhibit the PL. The PL peak energy and intensity increase with increasing the metal density on the a-Si because of the reduction in the grain size down to 2 nm. The photoluminescence energy and peak intensity depend strongly on the Secco etch time because the grain size is reduced by etching the grain boundaries.  相似文献   
44.
High power industrial multibeam CO2 lasers consist of a large number of closely packed parallel glass discharge tubes sharing a common plane parallel resonator. Every discharge tube forms an independent resonator. When discharge tubes of smaller diameter are used and the Fresnel numberN ≪ 1 for all resonators, they operate in waveguide mode. Waveguide modes have excellent discrimination of higher order modes. A DC excited waveguide multibeam CO2 laser is reported having six glass discharge tubes. Simultaneous excitation of DC discharge in all sections is achieved by producing pre-ionization using an auxiliary high frequency pulsed discharge along with its other advantages. Maximum 170 W output power is obtained with all beams operating in EH11 waveguide mode. The specific power of 28 W/m is much higher as compared to similar AC excited waveguide multibeam CO2 lasers. Theoretical analysis shows that all resonators of this laser will support only EH11 mode. This laser is successfully used for woodcutting  相似文献   
45.
A method using a focused ion beam (FIB) to prepare a silicon amorphous material is presented. The method involves the redeposition of sputtered material generated during the interaction of the Ga+ ion beam with a silicon substrate material. The shape and dimensions of this amorphous material are self-organized and reproducible. The stability of this amorphous material under electron irradiation was investigated in the transmission electron microscopy (TEM). Electron irradiation can induce recrystallization of the amorphous material, resulting in the lateral and vertical growth, starting at an amorphous-crystalline interface, of polysilicon containing defects.  相似文献   
46.
基于有限差分光束传播法的过渡波导功耗分析   总被引:1,自引:0,他引:1  
为了在既定尺寸下减小斜坡波导和弯曲波导的功耗,设计了4种过渡波导形状函数。用有限差分光束传播法(FD-BPM)进行了模拟分析,发现过渡波导形状的选取与坡度和曲折角存在条件有关,并给出了条件表达式及其详细说明。  相似文献   
47.
PECVDSiON薄膜的工艺控制,性质及其潜在应用   总被引:2,自引:1,他引:1  
祖继锋  余宽豪 《光学学报》1995,15(7):13-916
研究了等离子增强化学气相淀积氮氧化硅薄膜的工艺控制、性质以及薄膜波导在超大规模集成电路光互连中的潜在应用。  相似文献   
48.
祖继锋  邹立勋 《应用光学》1992,13(6):1-3,11
介绍超大规模集成电路(VLSI)波导(?)互连技术的最新进展,并预测其发展方向,以及如阿解决存在的实际问题。  相似文献   
49.
Hydroxyapatite Ca10(PO4)6(OH)2 (HAP) is known as a bioactive and biocompatible material, HAP coatings were used to improve the biocompatible of substrate by many researcher, In this work, HAP thin films on porous silicon (PS) substrates have been prepared by aqueous precipitation method with rapid thermal annealing (RTA) processes. The HAP films had been prepared under the annealing temperature ranging from 300 to 1000 °C. By the measurement of X-ray diffraction (XRD), it was found that for the crystallinity optimization, the heat-treatment at 850–950 °C for 1 h would be favorable. Atomic force microscopy (AFM) and scanning electron microscope (SEM) measurements reveal a dense and smooth surface of the HAP film, and tightly adherence of the coating on porous silicon substrate after sintered. Thus, by this method, porous silicon could be increased its bioactivity and so that could be used in the biomedical area.  相似文献   
50.
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