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探析了实验课程达不到预期培养目标的症结与成因,提出了将实验教学改革推向深入,实现课程教育培养功能的基本思路和举措。 相似文献
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Nonlinear cascade-configuration multi-wave mixing scheme based on electromagnetically induced transparency
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A nonlinear optical cascade-configuration multi-wave mixing (CCMWM) scheme is presented and analysed for the generation of coherent light in a six-level atomic system in the context of electromagnetically induced transparency (EIT). A detailed semi-classical study of the propagation of the generated mixing and probe fields is demonstrated. We show by numerical simulations that EIT is capable of suppressing linear and nonlinear photon absorption. The analytical dependence of the generated mixing field on the probe field and the respective detuning is also predicted. Such a nonlinear optical process can be used for generating coherent short-wavelength radiation. 相似文献
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文章探讨了电磁学课程中如何具体地发挥和凸现德育功能的有关问题,即明确育什么?如何育?在如何育的问题上重要的是结合教学的相关内容和环节,找到德育的“渗透点”。 相似文献
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Using Schrodinger-Maxwell formalism, we propose and analyze a continuous-wave four-wave mixing (FWM) scheme for the generation of coherent light in a six-level atomic system based on electromag-netically dual induced transparency. We derive the corresponding explicit analytical expressions for the generated mixing field. We find that the scheme greatly enhances FWM production efficiency and is also capable of inhibiting and delaying the onset of the detrimental three-photon destructive interference by choosing the proper decay rate in the second electromagnetically induced transparency (EIT) process. In addition, such an optical process also provides possibilities for producing short-wave-length coherent radiation at low pump intensities. 相似文献
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本文主要从课程理论的角度,分析探讨了当代全球性教育思潮和课程改革的动态与趋势,以指导普通高等师范院校理科当前的课程改革和建设,明确课程改革和建设的基本指导思想。 相似文献
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We discuss and analyze the absorption properties of a weak probe field in a typical four-level atomic system in the presence of a spontaneously generated coherence (SGC) term. The influences of the SGC and a coherent pump field on the probe absorption-amplification are investigated. The results show that the absorption of such a weak probe field can be dramatically enhanced due to the SGC effect. At the same time, the probe-absorption profile exhibits a two-peak structure and the probe-absorption peak gradually decreases as the pump intensity increases. On the contrary, the amplification of such a weak probe field near the line center of the probe transition can be achieved by adjusting the coherent pump field intensity in the absence of the SGC effect. 相似文献
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不确定度是评价测量质量的一个新概念。是误差理论研究的重大进展,不确定度表示是计量工作标准化的重要问题。本文介绍了不确定度概念及其对测量质量的基本定方法。 相似文献
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叙述了磷离子注入方法诱导具有不同发射波长的InGaAsP双量子阱结构的混合,并通过光致发光谱和断面透射电子显微术对量子阱混合的程度进行了研究。在特定条件下快速热退火处理后,光致发光谱显示,在离子注入剂量低于7×1011/cm2情况下,两个阱的谱峰能保持较好的分离,注入剂量从1011 /cm2增大到1012/cm2的过程中,两个阱的带隙蓝移值都似乎存在一个极大值,并且在同样的条件下,上阱(发射波长为1.52 μm)的带隙蓝移值较下阱(发射波长为1.59 μm)大些。当离子注入剂量达到1012/cm2时,上阱的谱峰近乎消失,双阱光致发光谱出现了一个谱峰。用断面透射电子显微术对原生长样品与带隙蓝移具有极大值的退火样品进行微结构比较,结果显示,对比原生长样品,退火样品的晶格原子基本得到修复,但阱与垒间的界面显得模糊,这说明离子注入导致两阱完全混合。 相似文献