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71.
Pseudo-spin-valves (PSV) structures, Ni83Fe17-3 nm / Co-2.5 nm / Au-t
Au / Co-2.5 nm, with 2.4t
Au3.2 nm were deposited by UHV magnetron sputtering. The weak ferromagnetic coupling J2×10-6 J/m2 between Ni-Fe/Co and Co layers and GMR effect 3% was found at RT. The GMR amplitude decreases monotonically from 5% at -100°C to 1% at 200°C. However, the slope of R(H) curve, i.e., GMR field sensitivity, is equal to about 1.5%/Oe and remains almost constant in the entire investigated temperature range. Additionally, our PSV display a good thermal stability, with no significant changes of magnetic and transport properties after annealing up to 250°C. 相似文献
72.
G. T. Vasilyuk S. A. Maskevich I. F. Sveklo A. E. German G. A. Gachko V. A. Liopo 《Journal of Applied Spectroscopy》2002,69(4):545-553
Using the methods of atomicforce microscopy, xray diffractometry, and spectrophotometry, we have studied the morphological, structural, and optical characteristics of GRSactive substrates based on original and annealed silver films. We show that the backing temperature during deposition is the factor which exerts the most substantial effect on the morphological and optical properties of silver films and also on their stability with time. The coefficients of the correlation of the deposition rate with the characteristics of the optical density spectra of silver films are calculated. It is found that hightemperature (350°C) annealing of a silver film leads to the selforganization of its surface into a quasiperiodic structure with semiellipsoidal islets. The contribution of the processes of excitation of plasma resonances to the formation of the optical density spectra is discussed. It is shown that as a result of thermal modification the concentration of the crystalline phase of silver in a silver film increases 2–3 times and also the dispersion of the orientation of crystallites decreases. 相似文献
73.
DONG Bing LEI Xiao-Lin CUI Hong-Liang 《理论物理通讯》2008,49(4):1045-1048
We report our studies of zero-frequency shot noise in tunneling
through a parallel-coupled quantum dot interferometer by employing
number-resolved quantum rate equations. We show that the combination of
quantum interference effect between two pathways and strong Coulomb
repulsion could result in a giant Fano factor, which is controllable by
tuning the enclosed magnetic flux. 相似文献
74.
Taking into account the quantum size effects and considering three types of scattering from bulk impurities,rough surface and rough interfaces,we use quantum-statistical Green‘s function approach and Kubo theory to calculate the electronic conductivity and the giant magnetoresistance in magnetic multilayered cylindrical systems.It is found that in the limit of weakly scattering from impurities surface and interfaces,the total conductivity is given by a sum of conductivities of all the subbands and two spin-channels.For each subband and each spin-channel the scattering rate due to the impurities,surface and interfaces is added up. 相似文献
75.
76.
77.
D. P. Belozorov A. G. Ravlik B. Z. Rameev S. T. Roschenko I. G. Shipkova S. I. Tarapov 《International Journal of Infrared and Millimeter Waves》2000,21(10):1627-1638
High frequency resonance technique was applied to study of magnetic multilayer Co/Cu films possess the giant magnetoresistance. The results of the ferromagnetic resonance study in 60GHz-80GHz and 1OGHz bands revealed low temperature changes of g-factor after annealing and a very small value of high frequency saturation magnetization. An abrupt change of the specimen impedance was registered in low field low field range for 10GHz. The static magnetic characteristics as hysteresis and magnetoresistance loops were obtained at room temperature for the planar orientation of external magnetic field. 相似文献
78.
79.
利用倒置显微镜研究电制备巨囊泡,并分析其形成和成长的动力学机理.由于磷脂头部的电特性,电场对水化的磷脂双层的静电力促使磷脂膜内双层之间分离.在动力学的作用下,双层两叶的不对称受力引发其弯曲、出芽、膨胀、封闭以及相互融合.结果表明,电场参数、干磷脂膜的均匀性、缓冲液以及温度等因素影响巨囊泡的粒径、形状和稳定性. 相似文献
80.
We show that the total variation mixing time of the simple random walk on the giant component of supercritical and is . This statement was proved, independently, by Fountoulakis and Reed. Our proof follows from a structure result for these graphs which is interesting in its own right. We show that these graphs are “decorated expanders” — an expander glued to graphs whose size has constant expectation and exponential tail, and such that each vertex in the expander is glued to no more than a constant number of decorations. © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 45, 383–407, 2014 相似文献