共查询到19条相似文献,搜索用时 500 毫秒
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表面等离子体能够增强氮化镓发光二极管的发光效率,为高效发光二极管芯片的研究提供了可行的方案。近年来,国内外研究小组在利用表面等离子体增强氮化镓发光二极管发光效率的实验中,取得了很多有价值的结果。介绍了具有金属薄膜、金属颗粒和金属光子晶体等典型结构的氮化镓发光二极管。重点探讨了表面等离子体增强发光二极管发光的机理、结构和关键技术。对具有二维金属光子晶体的氮化镓发光二极管发光增强机理进行了分析和预测,认为利用二维光子晶体可以从内量子效率和外量子效率两方面增强器件发光,并且有很好的可控制性,是提高发光效率的可行方案。 相似文献
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金属纳米二聚体结构的局域表面等离子体激元共振特性研究 总被引:3,自引:3,他引:0
将金属纳米粒子二聚体结构作为光学谐振腔,采用 时域有限差分(FDTD)法仿真模拟了一种新型局域表面等离子体激光器(SPASER)。 使用洛伦兹复介电常数模型研究二聚体的增益介质特性,探讨了二聚体结构中 两个纳米局域表面等离子体激元共振(LSPR)以及相互作用机制,进一步研究了 LSPR相互作用对SPASER的局域场增强的影响。 模拟结果表明,相比较单纳米颗粒SPASER,LSPR的相互作用使得二聚体SPASER的局域电场显著 增强,增强因子最 大可以相差27倍。本文研究为纳米光学器件尤其是激光器件的设计提 供了依据。LSPR效应的 研究可以用于探索一些光与物质相互作用的极限效 应,从而为有源光子线路、生物传感以及量子信息处理等研究开辟道路。 相似文献
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提高LED外量子效率 总被引:2,自引:2,他引:2
提高发光二极管的发光效率是当前的一个研究热点.简要介绍了从芯片技术角度提高发光二极管(IED)外量子效率的几种途径,生长分布布拉格反射层结构、制作透明衬底、衬底剥离技术、倒装芯片技术、表面粗化技术、异形芯片技术、采用光子晶体结构等.此外还介绍了发光材料、能带结构以及工艺对外量子效率的影响. 相似文献
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《中国激光》2015,(12)
用脉冲激光制备纳米硅的过程中,在Purcell腔中会形成等离子体晶格结构,这是等离子体激元与光子相互作用的结果,其形成的等离子体晶格与Wigner晶体结构很相似。利用光致发光光谱研究局域态发光特征从而去控制纳米硅结构的发光,在氧气或氮气环境下制备纳米硅样品,由于表面键合作用形成电子局域态会产生几个特征发光峰,分别位于560、600和700 nm附近。在氧气环境下用激光照射硅晶片形成硅量子点,可以观察到样品的拉曼光谱随着测量温度的增加而产生频谱移动,这个过程伴随着声子能量的变化。温度较高时,光致发光峰强度下降,同时发射频谱变宽。在77 K时,可以观察到光致发光峰的红移,这表明局域态发光在纳米硅发光的激活起着重要作用。在带隙中产生的局域态取决于表面键合的情况,表面键合可以激活硅量子点而增强发光。在硅薄膜上掺入稀土金属镱会形成电子局域态发光,可将电致发光的波长调控进入光通讯窗口。 相似文献
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基于表面等离激子受激辐射放大原理,提出了一种应用于表面增强拉曼散射(SERS)单分子探测的领结型纳米天线结构。采用有限元方法(FEM)研究其局域表面等离子体共振(LSPR)和SERS特性。结果表明,该领结型纳米天线的局域表面等离子体共振强度和局域电场强度得到明显的增强,其散射截面为非表面等离激子受激辐射放大领结型纳米天线的1.1×104倍,局域电场强度为1×102倍。同时,该领结型纳米天线的表面增强拉曼散射增强因子最大达到1016,足以进行精确的单分子探测;整个纳米天线表面的增强因子也可达到1012,足以应用于单个生物分子的探测。 相似文献
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InGaN-based light-emitting diode(LED)as for the replacement of conventional fluorescent lighting source still needs a great effort to improve the light-extracting efficiency as well as internal quantum efficiency of LEDs.Surface plasmon technology has recently attracted considerable interest,because the spontaneous emission rate and the light extraction efficiency of a light-emitting device can be simultaneously enhanced through the coupling between an InGaN quantum well and surface plasmons.The surface pla... 相似文献
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Wen-Hung Chuang Jyh-Yang Wang Yang C.C. Yean-Woei Kiang 《Photonics Technology Letters, IEEE》2008,20(16):1339-1341
We demonstrate the numerical study results of the enhancements of internal quantum efficiency (IQE) and external quantum efficiency (EQE) of a semiconductor quantum well when it is coupled with surface plasmons (SPs) induced on a grating interface between Ag and semiconductor. The IQE and EQE enhancements depend on the emission dipole position and the assigned intrinsic IQE. The SP dissipation in metal and the grazing-angle SP radiation lead to a significant difference between IQE and EQE. The enhancement of EQE is less significant when the intrinsic IQE becomes larger. In applying the SP coupling phenomenon to an InGaN-GaN quantum-well light-emitting diode, the efficiency enhancement is more significant in the green-red range, in which the intrinsic IQE is normally quite low. 相似文献
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The influence of capture effects on the characteristics of detectors of the ionizing radiation based on semi-insulating gallium
arsenide is considered. Generation of nonequilibrium electrons and holes along the entire thickness of the active region was
performed under illumination with an infrared light-emitting diode with a wavelength of 0.9 μm. In this case, the situation
emerging in the device structure under the effect of X-ray radiation or a high-energy electron beam was simulated. It is shown
that the variation in the shape of the output signal with time in this case is caused by variation in the electric field profile
due to the capture of holes at deep centers in gallium arsenide. An absolutely different distribution of the electric field
emerges in the structure under irradiation of a semitransparent cathode of the structure with a red light-emitting diode,
emission of which penetrates into the active region for mere 1 μm. In this case, the transformation of the electric field
is caused by the capture of electrons. Under the prolonged effect of such radiation, a space-charge-limited current mode emerges
in the device.
Original Russian Text ? G.I. Ayzenshtat, M.A. Lelekov, O.P. Tolbanov, 2008, published in Fizika i Tekhnika Poluprovodnikov,
2008, Vol. 42, No. 4, pp. 451–456. 相似文献
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共振腔发光二极管(RCLED)是一种新型发光二极管(LED)结构,同时具备了传统LED和垂直腔面激光器(VCSEL)两者的优点,具有良好的应用价值和广阔的市场前景.介绍了RCLED的基本原理和结构.以及器件结构的设计要点,指出发射波长650 nm的RCLED在塑料光纤(POF)通信领域的应用优势,可以作为民用数据通讯系统用光发射器件的首选.对近年来RCLED尤其是红光波长范围的RCLED发展情况进行了概述,同时指出我国在这一领域的研究现状. 相似文献
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《Organic Electronics》2007,8(2-3):136-147
Surface plasmon–polariton (SPP) modes may act as significant loss channels in organic light-emitting diode devices. We present experimental data illustrating that by the introduction of an appropriately scaled microstructure into a device, some of this lost power may be recovered as light. It is shown that in order to maximize this SPP-mediated light emission in a top-emitting light-emitting diode (TOLED) the plasmon modes associated with the two metal surfaces of the cathode must be coupled together. Data from grating-coupled and index-coupled SPP schemes are presented, and we show that photoluminescence emission from a structure containing a microstructured thin metal film that supports coupled SPPs is at least 50 times more effective than a similar planar structure. Experimental data is also presented from a structure containing a thin metal film whose profile contains a wavelength scale microstructure on a single interface. These data suggest that such a device geometry has the potential to increase the efficiency of top-emitting organic light-emitting devices. 相似文献
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Efficiency enhancement of organic light emitting diode via surface energy transfer between exciton and surface plasmon 总被引:1,自引:0,他引:1
Arunandan Kumar Ritu Srivastava Priyanka TyagiD.S. Mehta M.N. Kamalasanan 《Organic Electronics》2012,13(1):159-165
Organic light emitting diodes (OLEDs) with surface plasmon (SP) enhanced emission have been fabricated. Gold nanoclusters (GNCs) deposited using thermal evaporation technique has been used for localization of surface plasmons. Size of GNCs and distance of GNCs from the emissive layer have been optimized using steady state and time resolved photoluminescence (PL) results. 3.2 Times enhancement in PL intensity and 2.8 times enhancement in electroluminescence intensity of OLED have been obtained when GNCs of size 9.3 nm has been introduced at a distance of 5 nm from emissive layer. Distance dependence of energy transfer efficiency between exciton and SPs was found to be of 1/R4 type, which is typically the dependence for dipole-surface energy transfer. 相似文献
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本文综述了最近几年国内外聚合物发光二极管和激光器的研究进展状况和前景。对几种典型结构发光二极管和激光器做了简要介绍。并指出,这个领域虽然取得了很大成功,但仍有一些棘手的问题急待解决。 相似文献
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利用ZnO和GaN材料制备了ZnO:Al/n-ZnO/p-GaN透明电极异质结发光二极管。通过SEM、TEM和荧光光谱对ZnO纳米棒进行了结构表征和发光特性表征。通过半导体特性分析系统和光谱测试技术对ZnO:Al/n-ZnO/p-GaN异质结进行了电致发光性能测试和机理分析。结果表明该器件能产生有效的蓝紫色电致发光,其发光分别来自于n型ZnO、p型GaN以及界面辐射;并且采用ZnO:Al作为透明电极可以提高该器件的出光效率。该异质结可应用于高效率短波发光器件。 相似文献