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71.
为了避免光照对铟镓锌氧薄膜晶体管(InGaZnO thin film transistors,IGZO TFTs)电学特性的影响,IGZO TFT要增加遮光金属层.本文研究了遮光金属栅极悬浮时,IGZO TFT的输出特性.采用器件数值计算工具TCAD(technology computer-aided design)分析了IGZO层与栅介质层界面处电势分布,证实了悬浮栅(floating gate,FG)IGZO TFT输出曲线的不饱和现象是由悬浮栅与TFT漏端的电容耦合造成.基于等效电容的电压分配方法,提出了悬浮栅IGZO TFT电流的一阶模型.TCAD数值分析及一阶物理模型结果与测试具有较高程度的符合,较完整地解释了悬浮栅IGZO TFT的电学特性. 相似文献
72.
Shaolin Liao Ronald J. Vernon 《International Journal of Infrared and Millimeter Waves》2007,28(6):479-490
The newly developed Taylor-Interpolation-FFT (TI-FFT) algorithm dramatically increases the computational speeds for millimeter
wave propagation from a planar (cylindrical) surface onto a “quasi-planar” (“quasi-cylindrical”) surface. Two different scenarios
are considered in this article: the planar TI-FFT is for the computation of the wave propagation from a plane onto a “quasi-planar” surface and the cylindrical TI-FFT is for the computation of wave propagation from a cylindrical surface onto a “quasi-cylindrical” surface. Due to the
use of the FFT, the TI-FFT algorithm has a computational complexity of O(N
2 log2
N
2) for an N × N computational grid, instead of N
4 for the direct integration method. The TI-FFT algorithm has a low sampling rate according to the Nyquist sampling theorem.
The algorithm has accuracy down to −80 dB and it works particularly well for narrow-band fields and “quasi-planar” (“quasi-cylindrical”)
surfaces. 相似文献
73.
采用溶胶-凝胶法在SiO_2微球表面覆盖上一薄层Nd~(3+)掺杂SiO_2,并经电极放电熔融后形成表面光滑的高Q值微球.采用锥光纤将808 nm的抽运激光耦合入钕离子掺杂的高Q值微球形成回廊模,激发产生了1080—1097 nm波段受激辐射激光.由于所产生的激光有足够高的功率密度,在高Q SiO_2微球中激发产生了波长为1120—1143 nm一级自受激拉曼散射激光.推导了锥光纤掺钕微球组合的自受激拉曼散射的输出功率和阈值公式.描述了输出激光的特性:阈值、输出功率、线宽、边模抑制比. 相似文献
74.
W. Liu J.S. Wang X.L. Liao S.J. Zheng G.T. Ma J. Zheng S.Y. Wang 《Physica C: Superconductivity and its Applications》2011,471(5-6):156-162
To a high-Tc superconducting (HTS) maglev system which needs large levitation force density, the magnetized bulk high-Tc superconductor (HTSC) magnet is a good candidate because it can supply additional repulsive or attractive force above a permanent magnet guideway (PMG). Because the induced supercurrent within a magnetized bulk HTSC is the key parameter for the levitation performance, and it is sensitive to the magnetizing process and field, so the magnetized bulk HTSC magnets with different magnetizing processes had various levitation performances, not only the force magnitude, but also its force relaxation characteristics. Furthermore, the distribution and configuration of the induced supercurrent are also important factor to decide the levitation performance, especially the force relaxation characteristics. This article experimentally investigates the influences of different magnetizing processes and trapped fields on the levitation performance of a magnetized bulk HTSC magnet with smaller size than the magnetic inter-pole distance of PMG, and the obtained results are qualitatively analyzed by the Critical State Model. The test results and analyses of this article are useful for the suitable choice and optimal design of magnetized bulk HTSC magnets. 相似文献
75.
76.
77.
Room-temperature anomalous Hall effect and magnetroresistance in (Ga, Co)-codoped ZnO diluted magnetic semiconductor films 下载免费PDF全文
This paper reports that the(Ga,Co)-codoped ZnO thin films have been grown by inductively coupled plasma enhanced physical vapour deposition.Room-temperature ferromagnetism is observed for the as-grown thin films.The x-ray absorption fine structure characterization reveals that Co 2+ and Ga 3+ ions substitute for Zn 2+ ions in the ZnO lattice and exclude the possibility of extrinsic ferromagnetism origin.The ferromagnetic(Ga,Co)-codoped ZnO thin films exhibit carrier concentration dependent anomalous Hall effect and positive magnetoresistance at room temperature.The mechanism of anomalous Hall effect and magneto-transport in ferromagnetic ZnO-based diluted magnetic semiconductors is discussed. 相似文献
78.
Yan Xia Zhinong Gao Xueming Liao Wanying Wei Chenchen Pan 《Journal of nanoparticle research》2017,19(8):290
Acanthosphere-like gold microstructures (AGMs) were synthesized using a facile, two-step, seed-mediated method and butanediyl-1,4-bis(dimethylhexadecylammonium bromide) (16-4-16) as a structure-directing agent. The morphologies and sizes of the products were controlled during the synthesis process by adjusting the concentrations of 16-4-16, the AgNO3 feed, HAuCl4, ascorbic acid, the amount of Ag seeds and the types of gemini surfactants used through systematic inquiry; particle sizes ranging from 130 to 800 nm were well prepared. Correspondingly, the morphology of the products changed between regular and irregular AGMs, and the products presented a number of new morphologies, such as open-mouthed submicrostructures and ribbon nanowires. In particular, with the increase in the 16-4-16 concentration, the structural morphology of the thorns clearly changed from a tip to a lamellar structure. A UV-vis spectroscopic analysis indicated that the localized surface plasmon resonance (LSPR) peak of the AGMs could be adjusted by changing the above factors, which extended from 500 to 1350 nm in the near-infrared (NIR) region, enabling a tremendous potential for using the AGMs as platforms for various biomedical applications. Based on the intermediate products, we propose a two-stage growth mechanism for the AGMs in which their solid cores and tips are generated successively. Surface-enhanced Raman scattering (SERS) measurements indicate that the AGMs can serve as sensitive SERS substrates; a SERS detection limit of 5 × 10?7 M is presented for rhodamine B molecules. 相似文献
79.
80.
Mallamace F Gambadauro P Micali N Tartaglia P Liao C Chen S 《Physical review letters》2000,84(23):5431-5434
We show that percolation and structural arrest transitions coexist in different regions of the phase diagram of a copolymer-micellar system and relate them to short-range intermicellar attraction. The intermediate scattering function shows a nonergodic transition along a temperature and concentration dependent line. Analyses show a logarithmic time dependence, attributed to a higher-order glass transition singularity predicted by mode-coupling theory, followed by a power law. 相似文献