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961.
This paper presents a novel high-voltage lateral double diffused metal-oxide semiconductor (LDMOS) with self- adaptive interface charge (SAC) layer and its physical model of the vertical interface electric field. The SAC can be self-adaptive to collect high concentration dynamic inversion holes, which effectively enhance the electric field of dielectric buried layer (EI) and increase breakdown voltage (BV). The BV and EI of SAC LDMOS increase to 612 V and 600 V/tim from 204 V and 90.7 V/ttm of the conventional silicon-on-insulator, respectively. Moreover, enhancement factors of r/which present the enhanced ability of interface charge on EI are defined and analysed.  相似文献   
962.
The “far‐field” effect of metal nanoparticles (NPs), when chromophores localized nearby metal NPs (typically the distance >λ/10), is an important optical effect to enhance emission in photoluminescence. The far‐field effect originates mainly from the interaction between origin emission and mirror‐reflected emission, resulting in the increased irradiative rate of chromophores on the mirror‐type substrate. Here, the far‐field effect is used to improve emission efficiency of polymer light‐emitting diodes (PLEDs). A universal performance improvement is achieved for the full visible light (red, green, blue) PLEDs, utilizing gold (Au) NPs to modify the indium tin oxide (ITO) substrates; this is shown by experimental and theoretical simulation to mainly come from the far‐field effect. The optimized distance, between the NPs and chromophores with visible light emission ranging from 400 to 700 nm, is 80–120 nm. Thus the scope of the far‐field may overlap the light‐emitting profile very well to enhance the efficiency of optoelectronic devices. The 30–40% enhancement is obtained for different color‐emitting materials through distance optimization. The far‐field effect is demonstrated to enhance device performance for materials in the full‐visible spectral range, which extends the optoelectric applications of Au NPs.  相似文献   
963.
在铜(Cu)和非晶铟镓锌氧化物(a-IGZO)之间插入30 nm厚的钼(Mo)接触层, 制备了具有Cu-Mo源漏电极的a-IGZO薄膜晶体管(TFT). Mo接触层不仅能够抑制Cu与a-IGZO有源层之间的扩散, 而且提高了Cu电极与玻璃基底以及栅极绝缘层的结合强度. 制备的Cu-Mo结构TFT与纯Cu 结构TFT相比, 具有较高的迁移率(~9.26 cm2·V-1·s-1)、更短的电流传输长度(~0.2 μm)、更低的接触电阻(~1072 Ω)和有效接触电阻率(~1×10-4Ω·cm2), 能够满足TFT 阵列高导互联的要求.  相似文献   
964.
俞清  包伯成  徐权  陈墨  胡文 《物理学报》2015,64(17):170503-170503
采用常见元器件等效实现一个广义忆阻器, 进而制作出一个电路特性可靠的非线性电路, 有助于忆阻混沌电路的非线性现象的实验展示及其所产生的混沌信号的实际工程应用. 基于忆阻二极管桥电路, 构建了一种无接地限制的、易物理实现的一阶有源广义忆阻模拟器; 由该模拟器并联电容后与RC桥式振荡器线性耦合, 实现了一种无电感元件的忆阻混沌电路; 建立了无感忆阻混沌电路的动力学模型, 开展了相应的耗散性、平衡点、稳定性和动力学行为等分析. 结果表明, 无感忆阻混沌电路在相空间中存在分布2个不稳定非零鞍焦的耗散区和包含1个不稳定原点鞍点的非耗散区; 当元件参数改变时, 无感忆阻混沌电路有着共存分岔模式和共存吸引子等非线性行为. 研制了实验电路, 该电路结构简单、易实际制作, 实验测量和数值仿真两者结果一致, 验证了理论分析的有效性.  相似文献   
965.
王强  施红  胡明朗 《应用声学》2015,23(1):27-30
针对现有飞行安全监控体系中ACARS报文航迹点数量稀疏、分布不均匀、时延长,提出基于ADS-B技术实现实时、不间断飞行安全监控。首先,建立了基于ADS-B实时飞行安全监控体系架构,对飞行过程中存在的误操作进行实时检测并告警;然后,本着实用、可靠的原则,利用现有的计算机辅助软件,建立了ADS-B实时飞行安全半物理测试平台;最后,基于该平台建立了设计实时飞行安全监控系统的工程化、规范化流程。  相似文献   
966.
The transformation method provides an efficient way to control wave propagation by materials. However, the degree to which this transformation concept can be applied to other physical phenomena remains an open question. Recently, Hu et al. presented a general framework for determining the transformation relations of the physical quantities in an arbitrary partial differential equation (PDE) in its application scope according to the idea of the transformation method. In this paper, we will review the main concepts of this general theory, particularly the difference between this idea and usual methods. The flexibility of this method is shown using an example.  相似文献   
967.
牛嗣亮  廖毅  饶伟  胡永明 《光学学报》2012,32(1):106003-56
对于干涉型光纤法布里-珀罗(FFP)传感系统,外界环境对解调干涉仪的扰动是其主要噪声源之一。在光纤布拉格光栅构成的FFP传感系统中,对比分析了采用参考传感器和参考光源两种抗噪方法。实验结果表明,对于单频和宽带干扰,两种方法均可提高信噪比到40dB。而且由于采用窄线宽光纤激光器作为参考光源的噪声水平较低,其差分探测结果具有更好的抗噪效果。  相似文献   
968.
Sound relaxational absorption spectroscopy of excitable gas mixtures is potentially applied for gas composition detection. The relaxation of vibrational modes of gas molecules determines the sound relaxational absorption. However, to our knowledge, the contribution of each vibrational mode available in gas mixtures to sound multi-relaxation absorption has not been calculated in existing literature. In this paper, based on the decoupled expression of the effective isochoric molar heat for a gas mixture, a sound multi-relaxation absorption spectrum is decomposed into the sum of single-relaxation spectra. From this decomposable characteristic, the contribution of each vibrational mode available in the gaseous medium to the multi-relaxation absorption is obtained at room temperature. For various gas compositions including carbon dioxide, methane, nitrogen etc., the calculated contributions of vibrational modes are verified by the comparison with experiment data. We prove the following views with quantifiable outcomes that the primary molecular relaxation process associated with the lowest mode plays the major role in acoustic relaxational absorption of gas mixtures; the mode with lower vibrational frequency provides higher contribution to the primary relaxation process. This work could provide a deeper insight into the relationship between the sound relaxational absorption spectroscopy and gas molecules.  相似文献   
969.
In this paper, we present the investigations of electron paramagnetic resonance on perovskite manganite Pr0.5Sr0.5MnO3 and Ga-doped Pr0.5Sr0.5Mn0.95Ga0.05O3. The temperature dependent paramagnetic resonance spectra parameters (effective g-factor, peak-to-peak linewidth ΔH pp and double integrated intensities) have been used to study the paramagnetic spin correlations and spin dynamics. The gradual increase of effective g-factor is attributed to the presence of orbital ordering above T C. The model fittings of temperature dependent double integrated intensities reveal Arrhenius law is appropriate for describing Pr0.5Sr0.5Mn0.95Ga0.05O3 instead of Pr0.5Sr0.5MnO3 system. As for Pr0.5Sr0.5MnO3, the broadening of linewidth with the temperature increase origins from the contribution of small polaron hopping in the PM regime. However, as for Pr0.5Sr0.5Mn0.95Ga0.05O3, the broadening of EPR linewidth can be understood with the spin-lattice relaxation mechanism.  相似文献   
970.
胡利云  范洪义  张智明 《中国物理 B》2013,22(3):34202-034202
For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators(IWOP) technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented.  相似文献   
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