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We study the two samples of AlInGaN,i.e.,1-μm Gan grown at 1030℃ on the buffer and followed by a 0.6μm-thick epilayer of AlInGaN under the low pressure of 76 Torr and the AlInGaN layer deposited diectly on the buffer layer without the high-temperature GaN layer,by temperature-dependent photoluminescence(PL) spectroscopy and picosecond time-resolved photoluminescence(TRPL) spectroscopy.The TRPL signals of both the samples were fitted well as a stretched exponential decay at all temperatures,indicating significant disorder in the material.We attribute the disorder to nanoscale quantum dots or discs of high indium concentration.Temperature dependence of dispersive exponent β shows that the stretched exponential decay of the two samples comes from dfferent mechanisms.The different depths of the localization potential account for the difference,which is illustrated by the results of temperature dependence of radiative recombination lifetime and PL peak energy. 相似文献
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有机/聚合物白光电致发光器件 总被引:7,自引:3,他引:7
将聚合物材料作为空穴传输材料,以有机小分子蓝光染料1,1,4,4-四苯基丁二烯,绿光染料8-羟基喹啉铝和黄光染料5,6,11,12-四苯基四苯并作为产生白光所需要的三种色源,制备了有机/聚合物白光电致发光器件。这种器件的设计使聚合物的热电稳定性好的优点与有机小分子材料荧光效率高的优点相结合,拓宽了材料的选择范围,更有利于选择能带匹配的材料体系。器件的开启电压为2.5V左右,发光效率在9V时达到最大1.24lm/W,该电压下的亮度达到1600cd/m^2,器件的最大亮度超过20000cd/m^2(18V),器件最佳色度为(0.319,0.332),这在目前国际上有报道的有机/聚合物白光发光器件中居领先水平。 相似文献
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Fano-like quantum routing of single photons in a system with two waveguides coupled to two collocated atoms is investigated theoretically. Using a full quantum theory in real space, photonic scattering amplitudes along four ports of the waveguide network are analytically obtained. It is shown that, by adjusting the atomic dipole-dipole interaction, an evident Fano-line shape emerges in the scattering spectra of the single-dot configuration system.Moreover, Fano resonance can also be achieved by varying the atom-waveguide coupling strength and atomic detuning, in the presence of the atomic dipole-dipole interaction. Therefore, the atomic dipole-dipole interaction may be utilized as a possible way to control spectral Fano-like resonance. The feasibility with the experimental waveguide channels is also discussed. 相似文献
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物理实验教学应该重视的三个方面 总被引:2,自引:0,他引:2
实施素质教育的物理实验教学,是科学性与技术性的统一,本文从技术的角度立意,阐明了当今中学物理实验教学改革中应该重视的三个方面:操作技术,故障排除与反思心理。 相似文献
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We propose an approach to detect an unknown quantum state of the atom(s) by measuring the phase shifts of the transmitted photons through a dispersively-coupled cavity. In the framework of the input-output theory, we derive the relations between the phase shifts of the transmitted photons and the states of the atom(s) in the cavity. It is shown that due to the dispersive interaction between the cavity and the atom(s), information about the atomic state can then be extracted by measuring the phase shifts of the transmitted photons through the cavity. The feasibility of the proposal is also discussed with the experimental parameters by numerical method. 相似文献
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Si/SiNx/SiO2多层膜的光致发光 总被引:1,自引:0,他引:1
采用射频磁控溅射法,制备了具有强光致可见发光的纳米Si/SiNx/SiO2多层膜,利用傅立叶红外吸收(FTIR)谱,光致发光(PL)谱对其进行了研究。用260nm光激发得到的PL谱中观察到高强度的392nm(3.2eV)和670nm(1.9eV)光致发光峰,分析认为它们分别来自于缺陷态≡Si-到价带顶和从导带底到缺陷态≡Si-的辐射跃迁而产生的光致激发辐射复合发光。PL谱中只有370nm(3.4eV)处发光峰的峰位会受退火温度的影响,结合FTIR谱认为370nm发光与低价氧化物—SiOx(x<2.0)结合体有密不可分的关系。当SiO2层的厚度增大时,发光强度有所增强,800℃退火后出现最强发光,认为具有较大SiO2层厚度的Si/SiNx/SiO2结构多层膜更有利于退火后形成Si—N网络,能够得到更高效的光致发光。用量子限制-发光中心(QCLC)模型解释了可能的发光机制,并建立了发光的能隙态(EGS)模型。 相似文献
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Efficiently routing the quantum signals between different channels is essential in a quantum multichannel network.We investigate the quantum routing in a multi-cross-shaped waveguide coupled to driven three-level systems.Numerical results show that the high routing capacity transferring from the input channel to the other channels can be explicitly enhanced by effective reflection potentials. The proposed system may be utilized as a scalable quantum device to control single-photon routing. 相似文献
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研究AlInGaN材料的生长特性及其光学性质.通过对不同生长温度生长的三个AlInGaN样品的 测量,发现In的掺入量随着生长温度的降低而增加,而Al的掺入几乎没什么变化;在较低温 度下生长的材料具有较好的材料质量与光学特性,其原因直接与In组分的掺入有关,In组分 的掺入可以减少材料的缺陷,改善材料的质量.同时,用时间分辨光谱研究了AlInGaN材料的 发光机理,发现其发光强度随时间变化(荧光衰退寿命)不是指数衰减,而是一种伸展的指 数衰减.通过对这种伸展的指数衰减特性的研究,发现AlInGaN发光来自
关键词:
AlInGaN
MOCVD
局域激子
量子点 相似文献