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51.
1 Introduction  Inthe productionofverylargescaleintegration (VLSI) ,whenaCMOSchipiscutintobitslessthanonemicron ,thenumberofbitsaredeterminedbythediameteroftheconvergedbeam .Thesmallerthediameteris,thelargerthenumberwillbe,thusthecostofproductionisreduced .…  相似文献   
52.
TeOx薄膜结构及短波长静态记录特性的研究   总被引:4,自引:3,他引:1  
以真空蒸镀法在K9玻璃基底上制备了TeOx单层薄膜.使用X射线光电子能谱仪(XPS)、X射线衍射仪(XRD)、原子力显微镜(AFM)对薄膜的结构进行了分析.实验结果表明,薄膜是由晶态Te分散在非晶态TeO2基体中形成的混合体系,TeO2基体的存在增强了Te的抗氧化性能;薄膜具有精细粒状结构和粗糙的表面;退火后薄膜的反射率增加和Te向表面的偏析、重聚集及表面粗糙度的降低有关.采用波长为514.4nm的短波长静态记录仪对薄膜静态记录性能的测试结果表明:薄膜具有良好的记录灵敏性,在记录功率1.5mW、脉宽50ns时就可产生较高的反射率衬比(度).研究结果为选择合适掺和物使TeOx薄膜实际用作高密度光存储介质有重要意义.  相似文献   
53.
A novel method for producing rewritable optical memory with ultra-high storage density and ultra-high recording and readout speed is presented. A 120 fs, 800 nm, 1 kHz laser focused by an objective lens is used to produce recording bits in glass with high transmittance contrast. These recording bits can be erased by heat-treatment. The mechanism has been discussed by means of the absorption and electron spin resonance(ESR) spectra of silicate glasses before and after irradiation by the laser. The absorption of glasses increases greatly after irradiation because of color-center generation through multi-photon absorption. ESR spectra shows that the color-center induced in the glass are hole-trapped defects. The color-center disappears when the glass heated because the holes and electrons at traps are released by thermal stimulation and recombine again.  相似文献   
54.
姜淳  邓佩珍  张俊洲  干福熹 《光学学报》2000,20(9):287-1290
在国外报道的一些掺镱(Yb^3 )激发玻璃基上,实验研究得到发射截面更大的掺Yb^3 玻璃.其中掺Yb^3 锗碲酸盐`硼酸盐和硅铌酸盐玻璃的发射截面大于1.9pm^2;磷酸盐玻璃的发射截面较小但有较长的荧光寿命.优良的光谱性质使这些玻璃有望成为高平均功率和高峰值功率激光器增益介质的候选基质.  相似文献   
55.
给出了裸的及包裹SnO2纳米微晶的吸收、荧光和激发谱的实验结果。发现随着粒子尺寸的减小,包覆一层有机分子的SnO2纳米微晶的吸收谱带边向长波方向发生位移,这与裸SnO2纳米微晶的结果是不一致。表明纳米晶体的尺寸及其表面状态对它们的光谱性质有很大影响。从量子限域效应和介电限域效应两个方面对实验结果进行了讨论。  相似文献   
56.
In the present study, laser ablation inductively coupled plasma atomic emission spectroscopy (LA-ICP-AES) was successfully used to classify 26 ancient potash glass beads. These samples, mainly dated from the Han Dynasty to the Jin Dynasty, were from several provinces of both China and Vietnam. Quantitative analyses were done with both weathered and polished samples in order to consider the effects of surface weathering. Based on the characteristics of major, minor, and trace elements, we divided the samples into three subgroups (the percentage for each subgroup was 50%, 42%, and 8%, respectively) and also determined their main colorants. The results obtained provide new clues to trace the possible producing centers of ancient potash glasses in Asia. This study also reveals a complex network related to the trade of ancient potash glasses.  相似文献   
57.
Nondestructive Raman spectroscopy and external-beam proton-induced X-ray emission (PIXE) technique to analyze eight ancient glasses unearthed from the provinces of Henan,Hubei,and Jiangsu,which allowes for a good characterization of the glass matrix and chemical compositions,is carried out.The results indicate that all the eight glass samples could be typically divided into three systems: faience (sample No.SZWG-4),PbO-BaO-SiO 2 (sample Nos.NYWKI-5-1,HNWKII-88,and HNWKII-84),and Na 2 OCaO-SiO 2 (sample Nos.HBWKI-16,HBWKI-17,HBWKI-18,and SZWG-1).Additional relationships between the Raman spectra and parameters,such as residues of raw materials and opacifying agent,are also discussed by respectively comparing them with similar glass samples excavated from other historical sites.  相似文献   
58.
陈启婴  顾冬红 《光学学报》1995,15(12):717-1720
通过真空镀膜法在单晶硅制备了酞菁铜薄膜,在波长扫描和入射角可变全自动椭圆偏振光谱仪上研究了CuPc薄膜的椭偏光谱并分析了其电子结构。  相似文献   
59.
A novel wideband sensitive dry holographic photopolymer sensitized by rose bengal (RB) and methylene blue (MB) is fabricated, the holographic storage characteristics of which are investigated under different exposure wavelengths. The result shows that the sensitive spectral band exceeds 200 nm in visible light range, the maximum diffraction efficiency under different exposure wavelengths is more than 40% and decreases with the decrease of exposure wavelength, the exposure sensitivity is not change with the exposure wavelength.This photopolymer is appropriate for wavelength multiplexing or multi-wavelength recording in digital holographic storage.  相似文献   
60.
1.IntroductionDuringpastdecades,therehavebeenmanyproposalsforimplementingopticalParallelbinarylogicalprocuring.Thesemethodsmaybedividedintotwocategoriesaccordingtothenonlinearityintheprocessingsteps[1].(i)LinearencodingofinputvariablesandlogicoperationsarePerformedbymeansofnonlinearopticaldevices,suchasSSEEDslz].(n)NonlinearspatialencodingofvariablesandlogicoperationsPerformedbylinearopticalsystems,suchaspolarizationencodinginanimagingsystem['J,spatialcellcodinginashadow-castingsystem[4),t…  相似文献   
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