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1.
张乐天  刘士浩  谢文法 《发光学报》2015,36(11):1294-1299
通过在Ag层中引入一层Ge薄膜, 获得了具有低反射率和高反射相移的Ag/Ge/Ag复合阳极, 并制备了基于该阳极的蓝光顶发射有机电致发光器件.阳极高的反射相移使得器件在有机层厚度为100 nm时获得了顶发射蓝光发射, 且阳极较低的反射率减弱了器件内的微腔效应, 使得其电致发光光谱在不同视角下具有良好的稳定性.当Ge的厚度为20 nm时, 器件性能表现最为优良, 最高亮度和最大电流效率分别可达3 612 cd/m2和5.4 cd/A, 且色坐标在视角从0°变化到60°时仅移动了(0.007, 0.006).  相似文献   

2.
"利用对靶磁控溅射法制备了一系列Ag/Fe/Ag纳米薄膜,沉积态样品Fe层厚度固定为35 nm,Ag层厚度为1、2、3、4、5 nm.随后对沉积态样品进行了退火处理,退火温度分别为200、300、400、500、600 ℃ , 退火30 min. 利用VSM测量了样品的磁特性, 利用SPM观察样品表面形貌和磁畴结构,并且利用XRD分析了样品的晶体结构.研究结果表明,沉积态样品随Ag层厚度的变化,垂直和平行膜面矫顽力均先增加后减小.当Ag层厚度为3 nm时,垂直膜面矫顽力最大约为260 Oe,样品颗粒分布均  相似文献   

3.
A new growth model is introduced to describe surfactant-induced growth of Ag on Ag (111) with realistic physical parameters. In this model, the A-S exchange mechanism is considered for the first time. Using the Monte Carlo simulations, the influence of exchange mechanism, surface temperature T, the exchange barrier Eεx, and the coverage of surfactant θM on the growth mode and morphology during multilayer film growth of Ag/Ag (111) are studied in detail Both the referenced value of surfactant coverage and the method to obtain perfect layer-by-layer film in surfactantinduced Ag/Ag (111) system are provided. Our simulation results are consistent with many experimental observations for surfactant-induced growth of Ag on Ag (111).  相似文献   

4.
Ran GZ  Wen J  You LP  Xu WJ 《光谱学与光谱分析》2011,31(9):2324-2327
利用磁控溅射和热退火在硅衬底上制备了Ag纳米颗粒镶嵌的氧化硅薄膜(SiO2∶ Ag),制作了电致发光结构ITO/SiO2∶Ag/p-Si,观测到了可见区的电致发光.发现薄膜中的Ag纳米颗粒不仅成倍地提高器件的发光强度,还明显地移动电致发光的峰位.Ag含量越高,颗粒越大,发光峰位越红移.氧化硅中的发光中心与纳米Ag间的电...  相似文献   

5.
采用直流磁控溅射的方法制备了一系列(CoPt/Ag)n多层膜,然后在不同温度下 进行了退火处理,并对其结构和磁性做了初步的表征,研究了Ag的含量以及薄膜中每一单元 厚度与总厚度对退火后薄膜的结构以及磁性能的影响.结果表明,膜厚较薄时(大约20 nm)有 利于薄膜沿(001)取向生长,Ag的加入不但能够抑制CoPt晶粒的过分长大还可以诱导薄膜的( 001)取向,使退火后的薄膜在垂直于膜面方向上的矫顽力大大增强.对于特定组分为Co 40Pt43Ag17的薄膜,经600℃退火后已经显示了明显的(001) 取向,垂直于膜面方向上的矫顽力为5.6×105 A/m,饱和磁化强度为0.65T, 并 且磁滞回线具有很好的矩形度,剩磁比(s)为0.95. 关键词: 磁记录材料 磁性薄膜 CoPt/Ag纳米复合膜  相似文献   

6.
Localized surface plasmon resonance (LSPR) wavelength of metal nanoparticles (NPs) is highly sensitive to size, shape and the surrounding medium. Metal targets were laser ablated in liquid for preparation of spherical Ag and Ag@Au core–shell NP colloidal solution for refractive index sensing. The LSPR peak wavelength and broadening of the NPs were monitored in different refractive index liquid. Quasi-static Mie theory simulation results show that refractive index sensitivity of Ag, Ag–Au alloy and Ag@Au core–shell NPs increases nearly linearly with size and shell thickness. However, the increased broadening of the LSPR peak with size, alloy concentration and Au shell thickness restricts the sensing resolution of these NPs. Figure-of-merit (FOM) was calculated to optimize the size of Ag NPs, concentration of Ag–Au alloy NPs and Au shell thickness of Ag@Au core–shell NPs. The refractive index sensitivity (RIS) and FOM were optimum in the size range 20–40 nm for Ag NPs. Laser generated Ag@Au NPs of Au shell thickness in the range of 1–2 nm showed optimum FOM, where thin layer of Au coating can improve the stability of Ag NPs.  相似文献   

7.
用一维能带理论计算了清洁Ag(111),Ag(110)和Ag(001)表面的弛豫。计算结果显示出,当d1=2.640(膨胀4.2%)和d2=2.920(膨胀23.8%)〔对ng(111)〕;d1=1.375±0.008(收缩4.8%±0.008)[对Ag(110)」;d1=2.048±0.005(膨胀0.24%±0.005)[对Ag(001)〕时,理论计算的LEED谱与实验非常一致。  相似文献   

8.
Properties of the Ag/Ni/p-GaN structure at different temperatures are studied by Auger electron spectroscopy, scanning electron microscopy and high resolution x-ray diffraction. The effect of Ag in ohmic contact on the crystalline quality is investigated and the optimized value of annealing temperature is reported. The lowest specific contact resistance of 2.5 × 10^-4 Ωcm^2 is obtained at annealing temperature of 550^o C.  相似文献   

9.
杨海  杨黎东  马勇  杨智 《中国物理》2005,14(8):1665-1670
研究外场电压和纳米银粒子的尺寸对来自镶嵌在BaO薄膜中的纳米银粒子的光电发射的影响。在不同电压和不同尺寸条件下,计算了波长范围在 0.2到0.8μm的光电发射谱。给出了光电发射阈值对外场电压和纳米银粒子的尺寸依赖关系。同时认为在可见光范围中出现的光电发射是由于纳米银粒子的光学共振吸收所形成。这样的讨论有助于制备场助Ag-BaO光电薄膜的制备和工艺优化。  相似文献   

10.
Ag(111)与Ag(001)表面电子结构与稳定性的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
张海峰  李永平  潘必才 《物理学报》1996,45(11):1884-1889
采用LMTO-ASA方法,对几种不同方法获得的不尽相同的Ag(111)“稳定表面”的表面电子结构进行了系列对比研究,给出了这些不同表面弛豫结构的电子结构特性.根据表面能的大小,指出了最稳定表面结构应为单层向内弛豫表面,并对该类表面结构的电子结构特性作了分析和讨论.作为对比,还分析讨论了清洁理想Ag(001)表面的电子结构特性.根据Ag(111)和Ag(001)表面能的区别,指出Ag(001)表面较Ag(111)表面稳定  相似文献   

11.
TiO2 thin film synthesized by the RF sputtering method has been implanted by 120 keV Ag? ion with different doses (3?×?1014, 1?×?1015, 3?×?1015, 1?×?1016 and 3?×?1016 ions/cm2). Further, these were characterized by Rutherford back Scattering, XRD, X-ray photoelectron spectroscopy (XPS), UV–visible and fluorescence spectroscopy. Here we reported that after implantation, localized surface Plasmon resonance has been observed for the fluence 3?×?1016 ions/cm2, which was due to the formation of silver nanoparticles. Ag is in metallic form in the matrix of TiO2, which is very interestingly as oxidation of Ag was reported after implantation. Also, we have observed the interaction between nanoparticles of Ag and TiO2, which results in an increasing intensity in lower charge states (Ti3+) of Ti. This interaction is supported by XPS and fluorescence spectroscopy, which can help improve photo catalysis and antibacterial properties.  相似文献   

12.
采用熔融-淬火-放电等离子体烧结制备了Ag偏离化学计量比Ag1-xPb18SbTe20(x=0,0.25,0.50,0.75)样品,研究了Ag含量对样品热电传输性能的影响.结果表明,随Ag含量降低,样品中出现少量第二相Sb2Te3,样品载流子浓度增加到5×1018cm-3后不再增加.样品载流子迁移率随Ag含量降低先降低后增加,随着温度增加,载流子散射机理由电离杂质散射转变为声学波散射.随Ag含量降低,样品电导率增加而Seebeck系数降低,热导率增加.  相似文献   

13.
Polarization dependence of the coupling of excitation light to surface plasmon polaritons(SPPs) was investigated in a Ag nanoparticle–nanowire waveguide system(a Ag nanoparticle attached to a Ag nanowire). It was found that under the illumination of excitation light on the nanoparticle–nanowire junction, the coupling efficiency of light to SPPs depends on the polarization of the excitation light. Theoretical simulations revealed that it is the local near-field coupling between the nanoparticle and the nanowire that enhances the incident light to excite the nanowire SPPs. Because the shapes of the Ag nanoparticles differ, the local field intensity, and thus the excitement of the nanowire SPPs, vary with the polarization of the excitation light.  相似文献   

14.
吴黎黎  吴锋民 《中国物理 B》2010,19(6):66801-066801
A kinetic Monte Carlo simulation is performed in order to study the effect of Sb atoms as a surfactant on the growth of Ag on Ag(111). In our model the repulsive mechanism in which the surfactant Sb atoms repel diffusing Ag adatoms, and the exchange mechanism between Ag and Sb atoms, are considered. Our simulations show that the effects of Sb atoms for Ag/Ag(111) growth system are mainly to increase the chances for Ag atoms to overcome the Ehrlich--Schwoebel barrier both in the interlayer growth and along the edge diffusion. The influence of the coverage of Sb atoms and substrate temperature on the growth of Ag/Sb/Ag(111) is discussed.  相似文献   

15.
16.
采用Ag箔在两种不同的工艺条件下对YBCO高温超导块材进行了钎焊连接,钎焊完成后,分别对原始超导块材和钎焊接头进行磁悬浮力测量和俘获磁场测试、以评价钎焊质量.磁悬浮力的测试结果表明,在两种工艺条件下,钎焊接头的磁悬浮力分别可达原始块材的69.88%和79.37%.俘获场测试结果表明,单畴原始母材的俘获场为单峰,钎焊接头的俘获场为双峰;同时,钎缝区域的俘获磁场强度较低,没有完全恢复接头母材的超导环流,而限制了钎焊接头超导性能的提高.  相似文献   

17.
本报道了一种BPSCCO(2223)/Ag复合带的超导连接:将待连接的BPSCCO/Ag复合带的一宽平面Ag鞘部分掀开,彼此相向插入,并使暴露的BPSCCO芯相向叠接,在一定的单轴压力下进行冷压结,再经后续高温热处理。连接区在77.3K下能保持一定的超导载流能力。同时亦观察了连接区的I-V特性、抗弯曲应变和冷热疲劳应力的性能。  相似文献   

18.
The two-photon spectrum of the 21Ag ← 11Ag transition in trans-stilbene has been calculated at the complete active space self-consistent field (CASSCF) level of theory. Energies were obtained at the complete active space second-order perturbation (CASPT2) level of theory, while the geometries of both the initial and final states were optimized at the CASSCF level. The energy and the geometry optimizations were performed using an active space of 14 electrons in 14 active π orbitals. The vibrational frequencies of both states and the two-photon transition (TPT) cross-section were calculated with a smaller active space where the two lowest π orbitals were kept inactive. A newly implemented algorithm, in the quantum chemical package Molcas was used to determine the two-photon transition intensity. This method requires only the linear response of the CASSCF wavefunction. Furthermore, the vibronic structure of this TPT was studied. The Franck-Condon factors were obtained by calculating the overlap between the vibrational states involved, which were determined from the force fields of both the initial and final states, at the CASSCF level of theory. The results are in agreement with experiment.  相似文献   

19.
The sliver nanoparticles (AgNPs) with diameters of 30~50 nm were self-assembled onto the surfaces of reduced graphene oxide (rGO) sheets simply by mixing AgNO3 aqueous solution and GO dispersion via a synchronous reduction process. Structure and morphology of the rGO–AgNPs hybrids were well characterized. More significantly, the surface-enhanced Raman scattering (SERS) spectrum of 2-mercaptobenzimidazole (MBI) adsorbed on the solid rGO–AgNPs surface shown that the rGO–AgNPs system gives a very strong SERS intensity at in-plane vibrational modes in comparison to the out-of-plane vibrational modes. This large enhancement effect is most likely a result of charge-transfer (CT) mechanism. Based on the surface selection rules and the information provided by the highly enhanced in-plane vibrational modes, it can be found that MBI molecule was adsorbed on AgNPs surface as a thiol form via the sulphur and nitrogen atoms with a slightly tilted geometric conformation.  相似文献   

20.
利用时域有限差分法设计并分析了基于多孔氧化铝与纳米银颗粒的AAO/Ag NPs光吸收器模型,采用物理气相沉积方法制备了AAO/Ag NPs复合体系样品,表征并测试了不同实验参数下样品的光吸收特性.测试结果表明制备的AAO/Ag NPs复合体系样品在400~2 500nm波段的光吸收率高达98%,且高的光吸收率几乎不受银纳米颗粒氧化的影响.理论计算与测试分析表明多孔氧化铝孔内壁沉积的颗粒越多,沉积深度越深,沉积的银颗粒尺寸范围越大,光吸收率越高,而多孔结构有效降低了入射光的反射率,其表面的银膜有效降低了出射光的透射率.  相似文献   

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