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T.M. Nakatani Y.K. Takahashi M. Yamamoto 《Journal of magnetism and magnetic materials》2010,322(3):357-361
We have investigated the structure of Co2MnSi/MgO/Co2MnSi magnetic tunneling junctions with different tunnel magnetoresistance values depending on the in situ annealing temperatures just after the deposition of the upper Co2MnSi electrodes. The nano-beam diffraction patterns indicated that the degree of order of the upper Co2MnSi electrode annealed at 550 °C was higher than that of an electrode annealed at 400 °C. Moreover, the degree of the L21 order of the upper Co2MnSi electrode annealed at 550 °C was even lower than that of the lower Co2MnSi electrode annealed at an almost equal temperature of 600 °C. Atomic-scale observation using a high-angle annular dark-field (HAADF) method distinctly showed the existence of the L21-ordered regions in the B2-ordered matrix in the upper Co2MnSi electrode annealed at 400 °C. 相似文献
53.
在约瑟夫逊效应的理论研究中,大体上有微观和宏观两种方法。采用的是宏观的方法。利用推广的Ja-cobson方法,讨论了超导体/正常金属/半导体/正常金属/超导体结的约瑟夫逊效应,并在小电流假设下,推导出了该结的电流密度与位相之间的关系。 相似文献
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An immiscible liquid–liquid multiphase flow in a cross‐junction microchannel was numerically studied using the lattice Boltzmann method. An improved, immiscible lattice BGK model was proposed by introducing surface tension force based on the continuum surface force (CSF) method. Recoloring step was replaced by the anti‐diffusion scheme in the mixed region to reduce the side‐effect and control the thickness of the interface. The present method was tested by the simulation of a static bubble. Laplace's law and spurious velocities were examined. The results show that our model is more advantageous for simulations of immiscible fluids than the existing immiscible lattice BGK models. Computational results of multiphase flow in a cross‐junction microchannel were obtained and analyzed based on dimensionless numbers. It is found that the flow pattern is decided mostly by the capillary number at a small inlet flux. However, at the same capillary number, a large inlet flux will lead to much smaller droplet generation. For this case, the flow is determined by both the capillary number and the Weber number. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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ZHAO Xu LIANG Xian-Ting 《理论物理通讯》2005,44(5):827-832
We investigate the short-time decoherence of a solid-state qubit under Ohmic noise at optimal operation points. The decoherence is analyzed by maximum norm of the deviation density operator. It is shown that at the temperature T = 3 mK, the loss of the fidelity due to decoherence is much smaller than the DiVincenzo low decoherence criterion, which means that the mode/may be an optimal candidate of qubit for quantum computation. 相似文献
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A moderately hydrophobic ionic liquid, tributyl(2-methoxyethyl)phosphonium bis(pentafluoroethanesulfonyl)amide ([TBMOEP+][C2C2N−]), shows a very stable liquid junction potential upon contact with an aqueous solution whose ionic strength is as low as 1 μmol dm−3. The stability with the maximum excursion of the potential within ±0.5 mV for 30 min is very promising for accurate determination of pH and other single ion activities potentiometrically. 相似文献
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介绍了验证PN结伏安关系特性实验的实验原理,并利用绘图软件Origin7.5对实验数据进行处理.结果表明,PN结的扩散电流和两端的正向电压之间满足指数关系.通过与理论公式的比较,准确地测出了玻尔兹曼常数. 相似文献
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