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表面等离激元是束缚在金属—介质交界面上的一种电磁波模式,可突破衍射极限,被认为是下一代集成光子回路最有希望的信息载体。基于我们的研究工作,就几种表面等离激元金属狭缝结构的原理和应用做了简单概述。利用法布里-波罗谐振腔、法诺共振、多模干涉等光学效应,这些金属狭缝结构可对表面等离激元的传输行为进行有效地调控。在理论上和实验上,利用金属狭缝结构实现了亚波长表面等离激元单向激发器、亚微米宽带单向激发器、亚微米分束器、超紧凑纳米聚焦器件和亚微米全光开关等纳米光子器件。这些纳米光子器件在纳米集成光学中具有重要应用。 相似文献
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我们提出了一种利用太赫兹表面等离激元对放置在半导体表面的生化薄膜进行光谱测量的新方法。我们从理论上证明了半导体材料对其上传输的太赫兹表面等离子体波具有较强的表面束缚性,从而提高太赫兹波与半导体表面的生化薄膜之间的相互作用。通过采用太赫兹时域光谱测量系统,我们从实验上分别得到了洋葱表皮的太赫兹表面等离子体波和自由空间太赫兹波透射波谱。实验结果表明,当测量对象是厚度仅为自由空间太赫兹波波长的约百分之一的单层洋葱表皮时,表面等离子体波的透射波谱与自由空间太赫兹波透射波谱相比具有更加多的特征吸收峰。 相似文献
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《红外与毫米波学报》2016,(6)
提出了一种利用太赫兹表面等离激元对放置在半导体表面的生化薄膜进行光谱测量的新方法.从理论上证明了半导体材料对其传输的太赫兹表面等离子体波具有较强的表面束缚性,从而提高太赫兹波与半导体表面生化薄膜之间的相互作用.通过采用太赫兹时域光谱测量系统,从实验上分别得到了洋葱表皮的太赫兹表面等离子体波和自由空间太赫兹波透射波谱.实验结果表明,当测量对象是厚度仅为自由空间太赫兹波波长约1%的单层洋葱表皮时,表面等离子体波的透射波谱与自由空间太赫兹波透射波谱相比具有更加多的特征吸收峰. 相似文献
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重点介绍了采用表面等离子体增强效应的近场光刻制作亚微米结构的二维点阵图形的技术。在研究亚波长纳米孔阵列超透射现象基本原理的基础上,应用有限差分时域(FDTD)算法数值模拟了周期性孔阵列的电场强度分布,讨论了纳米孔阵列所激发的表面等离子体激元提高近场光刻分辨率的微观机制。以金膜上的亚波长纳米孔阵列作为掩模版进行了接触式曝光实验,实际制作出了光刻胶的亚波长二维点阵图形,点阵图形的直径约为300nm,周期约为700nm。这种新型的微纳加工技术具有应用简单、成本低等特点,在大规模二维纳米点阵的制作方面有一定的应用潜力。 相似文献
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提出了一种基于新型人工表面等离子体激元(Spoof Surface Plasmon Polaritons, SSPPs)馈电带有引向器的低剖面宽带八木天线阵列。天线阵列包括两部分:基于人工表面等离子体激元波导的四路宽带功分器和八木天线阵列。人工表面等离子体激元具有高的场局限性,将信号束缚在人工表面等离子体激元的凹槽结构中保证了信号的高效传输,减少了传输损耗。八木天线通过进一步加载引向器结构能够实现端射辐射特性。测试结果表明:天线阵列的回波损耗在4.5 ~6.05 GHz 频率范围内小于-10 dB。天线阵列实际增益在4.5 ~ 6.05 GHz 范围内最高可达11.1 dBi。 相似文献
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表面等离激元共振衰减诱导热电子,因其能量高、分布窄、打破半导体禁带宽度限制等特点被广泛应用于拓展半导体光电转换的响应光谱,如拓展宽禁带半导体的响应光谱至可见光波段,拓展硅的响应波段至近红外。此外,还可以通过调节表面等离激元结构调控响应光谱和实现偏振探测,在实现硅基近红外光电探测领域具有重要的应用价值。从表面等离激元以及表面等离激元内光电效应的机理出发,综述了表面等离激元热电子原理在实现硅基近红外光电探测方面的研究进展,并总结了表面等离激元结构的形貌,尺寸、分布等因素对热电子的产生(外量子效率)和注入效率(内量子效率)的影响。最后展望了基于表面等离激元结构的硅基肖特基结近红外光电探测的研究方向。 相似文献
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利用自洽线性场理论:考虑电子的三维扰动,分析了轴向实心相对论电子注通过填充背景等离子体介质筒慢波波导产生的切伦可夫辐射,导出了描述其不稳定性的色散方程和注液互作用的同步条件,求得出电磁波辐射的时间增长率,分析了背景等离子体密度和实心电子注半径对波增长率的影响。 相似文献
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利用一些醛类固定液在固定作用中可产生荧光物质的特性,在荧光显微术中选择合适的激发波长和发射波长,使得一些未经荧光标记的生物组织结构也能在激光扫描共聚焦显微镜下成像,并可进行三维图像的构建,这不仅使激光扫描共聚焦显微技术的运用范围大为扩展,而且大大节约了研究费用和时间,提高了效益。此外,该技术还为组织学和细胞学的回顾性研究提供了一个有效手段,并将激光扫描共聚焦显微技术与普通光镜及电镜技术有机地结合起来,使组织和细胞的形态学研究得以全方位进行。 相似文献
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氮化物异质结电子气的二维特性和迁移率 总被引:5,自引:6,他引:5
薛舫时 《固体电子学研究与进展》2007,27(1):1-6,12
从自洽求解薛定谔方程出发,计算了氮化物异质结中的二维电子气、退局域态和二维表面态。研究了电子气二维特性与迁移率间的关联。用电子气的二维特性和沟道电子向表面态溢出模型解释了室温和低温下迁移率随电子浓度变化的行为。以电子迁移率与异质结构间的关联为依据,提出了优化设计异质结构来增大电子迁移率和降低迁移率随电子浓度变化的新思路。 相似文献
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A method for the measurement of the resistivity of semiconductor samples is described which uses the electron beam of a scanning electron microscope as probe. This technique provides high local resolution (about 10 μm), causes no damage of the semiconductor material and is fast so that the two dimensional distribution of the resistivity can be plotted on a cathode ray tube. The sample, however, must be prepared to have a large area blocking Schottky-contact. The focussed electron beam generates carriers in a space charge region below a thin metal contact. The measurement is based on the change of the I-V characteristic of the Schottky diode caused by the spreading resistance from the point of the carrier generation to the bulk. Experimental results are presented as well as a theoretical evaluation of the sensitivity of this measuring technique. 相似文献
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Non-linear rectification of the Rf electric fields excited in a convectively amplifying electron beam-plasma interaction results in a DC electric field and corresponding ponderomotive force acting on the charged particles to produce a space-charge separation i.e. a type of plasma double-layer. This paper analysis the effect, taking into account plasma electron temperature and electron-neutral collisions. To measure such double-layers an electron beam probe constitutes a convenient non-perturbing diagnostic technique, but great care is required in its calibration. An analysis is presented taking into account significant non-linear effects which had been neglected in previous work. The paper concludes with some preliminary experimental results illusrating the use of the technique in a beam-plasma interaction for which a weak double-layer electric fields is predicted. 相似文献
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Electron beam pre-patterning for site-control of self-assembled InAs quantum dots on Inp surfaces 总被引:2,自引:0,他引:2
M. Borgström T. Bryllert B. Gustafson J. Johansson T. Sass L. E. Wernersson W. Seifert L. Samuelson 《Journal of Electronic Materials》2001,30(5):482-486
A site control technique for individual InAs quantum dots (QDs) formed by self-assembling has been developed, using scanning
electron microscope (SEM) assisted nano-deposition and metal organic vapor phase epitaxy (MOVPE). In a first step we characterize
a device with randomly distributed InAs QDs on InP, using resonant tunneling and transmission electron microscopy (TEM). Secondly,
we use nano-scale deposits, created at the focal point of the electron beam on an InP based heterostructure, as “nano growth
masks”. Growth of a thin InP layer produces nano-holes above the deposits. The deposits are removed by oxygen plasma etching.
When InAs is supplied on this surface, QDs are self-assembled at the hole sites, while no InAs dots are observed in the flat
surface region. A vertical single electron tunneling device is proposed, using the developed technique. 相似文献
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Pattern writing on insulating materials (e.g. quartz) using electron beam lithography (EBL) is a challenging task and it is even more difficult when the pattern is three dimensional (3D). Surface charging trapped on insulating substrates may deflect the electron beam during electron beam pattern writing causing undesired effects.In this work, the surface charging has been suppressed by top coating with water soluble conductive polymer layer using poly (3,4-Etylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS). The 3D masking profiles are created on a negative tone photoresist (Microresist, ma-N2403) using Raith150 EBL tool with variable dose controlled beam exposure. The 3D patterns have been transferred onto the quartz substrate by single step reactive ion etching (RIE) with suitable resist to substrate selectivity.We have demonstrated the fabrication of 3D geometrical shapes such as pyramids, hemispheres, and cones with dimensions down to 300 nm using this technique without any surface charging effects. 相似文献