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41.
采用溶胶凝胶法成功制备了SrTiO3∶Pr3+、SrTiO3∶Pr3+, Mg2+ 及SrTiO3∶Pr3+, Al3+荧光粉.通过XRD、PL谱及第一性原理计算对样品的晶体结构、光谱特性及发光增强机制进行了研究.研究结果表明：共掺杂后,SrTiO3∶Pr3+荧光粉为单一组成的SrTiO3立方相,主发射锋位于617 nm, 对应于Pr3+离子的1D2→3H4跃迁发射.SrTiO3∶Pr3+, Mg2+ 及SrTiO3∶Pr3+, Al3+荧光粉的发光强度分别是SrTiO3∶Pr3+荧光粉发光强度的7倍和2倍,但主要发光机制没有改变.Mulliken布局分析表明,Mg2+、Al3+离子的掺入使SrTiO3∶Pr3+荧光粉中Ti-O及Pr-O键的化学键增强、键长变短,SrTiO3∶Pr3+基质向Pr3+离子发光中心的能量传递效率提高,导致SrTiO3∶Pr3+, Mg2+ 及SrTiO3∶Pr3+, Al3+荧光粉的发光效率提高. 相似文献
42.
偏硅酸钙中Pr3+的4f5d态的光谱特性及Pr3+→Gd3+的能量传递 总被引：2，自引：0，他引：2
合成了高效发射UV光的CaSiO3:Pr^3 新型荧光体,研究了室温下Pr^3 的4f5d态的发射和激发光谱,Pr^3 的4f5d态的最低子能级向4f^2组态的^3H4,^3H6和^1G4能级跃迁产生UV发射,并不伴随有4f-4f能级跃迁的可见光发射。Pr^3 的浓度猝灭是由于辐射和无辐射能量传递造成的,同时,在CaSiO3中,存在Pr^3 →Cd^3 的能量传递,探讨了其能量传递特性。 相似文献
43.
We present a rigorous solution for the problem of diffraction at a locally deformed plane wave-guide. This method can be applied to the study of mode coupling and mode conversion. 相似文献
44.
Sangsu Park Seungjae Jung Manzar Siddik Minseok Jo Jubong Park Seonghyun Kim Wootae Lee Jungho Shin Daeseok Lee Godeuni Choi Jiyong Woo Euijun Cha Byoung Hun Lee Hyunsang Hwang 《固体物理学:研究快报》2012,6(11):454-456
We propose a selector‐less Pr0.7Ca0.3MnO3 (PCMO) based resistive‐switching RAM (RRAM) for high‐density cross‐point memory array applications. First, we investigate the inhomogeneous barrier with an effective barrier height (Φeff), i.e., self‐formed Schottky barrier. In addition, a scalable 4F2 selector‐less cross‐point 1 kb RRAM array has been successfully fabricated, demonstrating set, reset, and read operation for high cell efficiency and high‐density memory applications. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
45.
Christian Camus Daniel Abou‐Ras Nicholas A. Allsop Sophie E. Gledhill Tristan Khler Jrg Rappich Iver Lauermann Martha C. Lux‐Steiner Christian‐Herbert Fischer 《physica status solidi (a)》2010,207(1):129-131
In this paper, the incorporation of carbon into CuInS2 (CIS) thin films is described as observed in spray ion layer gas reaction (ILGAR) deposition of such thin films. It is shown that this carbon incorporation leads to the formation of a CIS–carbon multilayer stack. Its growth mechanism is explained by the interaction of the copper and indium precursor compounds used in the deposition process. 相似文献
46.
D. N. Muraviev J. Macans M. J. Esplandiu M. Farre M. Muoz S. Alegret 《physica status solidi (a)》2007,204(6):1686-1692
In this paper we report the novel simple route for the inter‐matrix synthesis and characterization of Polymer Stabilized Metal Nanoparticles (PSMNPs) with core‐shell structure. The proposed approach is based on the use of functionalized polymeric membranes (FPM) as a nanoreactor for both to synthesize and to characterize the composition and morphology of PSMNPs. The desired functionalization is achieved by the chemical grafting of the desired functional groups (sulphonic in our case) to the polymeric matrix. The proposed approach is illustrated by the results obtained by studying the intermatrix synthesis of Pt@Cu‐core‐shell PSMNPs of different compositions in sulfonated poly(ether ether ketone) (SPEEK) membranes. The electrochemical response of amperometric sensors prepared by using SPEEK‐Pt@Cu‐PSMNP nanocomposite membranes as a sensing element has been shown to increase with the loading of the shell‐forming metal (Pt). The presence of Pt@Cu‐PSMNC inside the membrane not only substantially improves the electric conductivity of the polymer, but also testifies to manifestation of clearly pronounced strong electrocatalytic activity of Pt@Cu‐PSMNC towards analyte under study (H2O2). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
47.
C. Toma A. Volodin G. Bogdan W. Deferme K. Haenen M. Nesldek C. Van Haesendonck 《physica status solidi (a)》2007,204(9):2920-2924
The influence of the voltage applied to the tip of an atomic force microscope (AFM) on the local modification of the surface of CVD‐grown diamond films is studied. By applying a negative voltage to the conductive (highly doped) silicon AFM tip, two kinds of patterns can be created. In the voltage range –6 V to –10 V structures that are elevated with respect to the surface (creation of bumps) are obtained, while at higher voltages (–12 V to –15 V) the patterns are scribed into the diamond surface (creation of pits). The origin of the observed modifications is discussed in terms of an electrochemical process that is enhanced by local heating occurring due to severe current crowding. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
48.
Stphanie Pace Laetitia Gazagnes Philippe Gonzalez Claude Guimon Michel Granier Didier Cot Jean‐Marie Devoisselle Frdrique Cunin 《physica status solidi (a)》2009,206(6):1326-1329
A new approach for the selective chemical modification of porous silicon surfaces with organic monolayers is reported. The organic layers are first covalently grafted onto (100) surface of hydrogen terminated silicon via thermal hydrosilylation of alkene or functionalized alkene molecules yielding stable monolayers on flat Si surfaces. The functionalized silicon surfaces are then electrochemically etched in a hydrofluoric acid solution. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
49.
B. Ashcroft B. Takulapalli J. Yang G. M. Laws H. Q. Zhang N. J. Tao S. Lindsay D. Gust T. J. Thornton 《physica status solidi b》2004,241(10):2291-2296
The threshold voltage characteristics of a buried channel silicon‐on‐insulator MOSFET is examined in solutions of varying acidity. Experiments utilizing an integrated micro‐fluidic channel exhibit a variation in threshold voltage that appears approximately linear with pH in the range from pH 4 to pH 7, with a sensitivity of ∼1 V per pH unit. Charge configuration changes in the vicinity of the MOSFET inversion layer due to protonation/deprotonation of the device surface is proposed as an explanation for the observed shifts in threshold voltage. When the pH range is expanded we observe a non‐linear relationship bet‐ ween pH and the threshold voltage of the device, this behavior is explained in terms of deprotonation of the different species of the native oxide surface, Numerical simulations of the MOSFET demonstrate that the threshold voltage sensitivity corresponds to an additional surface positive fixed charge density of ∼ 1 × 1010 cm–2 for each pH unit. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
50.
Composite systems containing semiconductor nanocrystals (NCs) embedded into a conducting polymer matrix have a number of key distinctions from semiconductor quantum dot heterostructures. Low electron affinity of conducting polymers results in a type‐II heterojunction at the NC‐polymer interface with electrons localized inside NC and delocalized holes with a continuous density of states. Optical properties of nanocomposites were considered accounting for the above‐mentioned features of energy spectrum. The results explain a series of experimentally observed peculiarities including various and sometimes featureless absorption spectra, large Stokes shift and activationless photoconductivity. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献