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排序方式: 共有2864条查询结果,搜索用时 18 毫秒
31.
ZHANG Xinliang HUANG Dexiu SUN Junqiang SUN Junqiang LIU Deming YI Heqing 《Chinese Journal of Lasers》2000,9(6):510-514
1 Introduction Cross gainmodulation (XGM )insemiconductoropticalamplifiers (SOAs)isoneofthemostefficientwaystoachieveall opticalwavelengthconversionandhassimpleimplementation ,largewavelengthconversionspan ,highconversionefficiency[1] andextremelyhighbitrate… 相似文献
32.
A fixed point index is defined for mappings defined on a cone which do not necessarily take their values in but satisfy a weak type of boundary condition called generalized inward. This class strictly includes the well-known weakly inward class. New results for existence of multiple fixed points are established.
33.
(In,Mn)As nanowires with ultrahigh Mn concentration have been successfully grown on GaAs(001) substrates by molecular beam epitaxy. The morphology dependences on Mn concentration and growth temperature are investigated. High Mn concentration and high growth temperature are both necessary for the growth of nanowires. All the (In,Mn)As nanowires are self-aligned along [−110]GaAs, and therefore have the shape magnetic anisotropy with the easy axis along the alignment orientation of the nanowires. 相似文献
34.
In the present work, a review of the metallic (M) and semiconducting (S) separation of single‐wall carbon nanotubes (SWCNTs) using polysaccharide gels is presented. First, the progress of the M/S separation is described, including the following: the discovery of high‐yield separation using agarose gel electrophoresis, the separation of SWCNTs without an electric field, such as through the use of the freeze and squeeze method, the development of continuous separation using column chromatography, and the single‐chirality separation of SWCNTs using a multicolumn with dextran‐based gel. Next, the separation mechanism using gel is discussed, in which separation is achieved by selective adsorption of S‐SWCNTs by gel with a specific combination of surfactant and gel. Lastly, future directions for the separation of SWCNTs and for the use of the separated SWCNTs are discussed.
35.
《Current Applied Physics》2014,14(2):161-165
The J–V characteristics of the Au/5,10,15, 20-tetraphenyl-21H, 23H-porphine iron (III) chloride (FeTPPCl)/ITO device exhibits rectifying behavior in the dark which can be explained due to the formation of Schottky barrier at ITO/FeTPPCl junction and the typical junction parameters were estimated in temperatures from 302 to 368 K. The temperature dependence of DC electrical conductivity showed that FeTPPCl films behave as semiconducting materials. These results indicate that the DC electrical conduction is through an activated process having three conduction mechanisms in the investigated range of temperatures. A variable range hopping model, a polaron model and band to band transitions have been used to explain the conduction mechanisms for FeTPPCl films. 相似文献
36.
37.
吴斌 《数学物理学报(B辑英文版)》2011,31(3):960-968
In this paper, we consider a degenerate steady-state drift-diffusion model for semiconductors. The pressure function used in this paper is ()(s) = s~α(α > 1). We present existence results for general nonlinear diffhsivities for the degenerate Dirichlet-Neumann mixed boundary value problem. 相似文献
38.
A Solution‐Processed Air‐Stable Perylene Diimide Derivative for N‐type Organic Thin Film Transistors
Heng‐Wen Ting Szu‐Ying Chen Tin‐Chun Huang Prof. Jeng‐Hua Wei Prof. Tri‐Rung Yew 《Chemphyschem》2011,12(4):871-877
For future all‐soluble organic thin film transistor (OTFT) applications, a new soluble n‐type air‐stable perylene diimide derivative semiconductor material with (trifluoromethyl)benzyl groups (TC–PDI–F) is synthesized. The film is formed by spin‐coating in air and optimized for OTFT fabrications. The transistor characteristics and air‐stability of the TC–PDI–F OTFTs is measured to investigate the feasibility of using solution‐processed TC–PDI–F for future OTFT applications. For all‐solution OTFT process applications, the transistor characteristics are demonstrated by using TC–PDI–F as an n‐type semiconductor material and liquid‐phase‐deposited SiO2 (LPD–SiO2) as a gate dielectric material. All processes (except material synthesis and electrode deposition) and electrical measurements are conducted in air. 相似文献
39.
有机硅化合物和有机硼化合物在有机半导体材料中的应用 总被引:1,自引:0,他引:1
有机硅化合物和有机硼化合物是有机化学中2类非常重要的化合物,它们在有机合成化学和材料化学等领域都有着广泛的应用。有机半导体材料是一个新兴的研究领域,这2类化合物在这个新兴领域中也有着独特的贡献。简单介绍了有机硅化合物和有机硼化合物在有机半导体材料中的应用。 相似文献
40.
作为半导体材料的金刚石具有宽的禁带宽度和高的热导率、介质击穿场强等优异性质,因此其应用前景广阔.P型金刚石发展较N型金刚石成熟.因为缺乏可实用的N型金刚石材料,这使得金刚石半导体器件的应用难以实现.因此N型半导体金刚石成为研究者关注的焦点.论文从掺杂元素和制备方法两方面详细介绍了国内外N型金刚石的研究现状.硼与磷或硫元素共掺杂获得N型金刚石的研究取得了较大进展;利用化学气相沉积法和离子注入法制备N型半导体金刚石研究较多且取得了一定进展.高压高温下的温度梯度法便于掺杂调控金刚石性能,因而利用该法合成N型半导体金刚石大单晶值得尝试. 相似文献