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91.
利用磁控溅射方法在100℃的MgO单晶基片上制备了[FePt/Au]10多层膜,并研究了采用FePt/Au多层膜结构对FePt薄膜的有序化温度、矫顽力(HC)、垂直磁各向异性、晶粒尺寸以及颗粒间磁交换耦合作用的影响.磁性测试结果表明:FePt/Au多层膜在退火后具有较高的HC、良好的垂直磁各向异性、较小的晶粒尺寸且无磁交换耦合作用.截面高分辨电镜分析表明:Au可以缓解MgO和FePt之间较大的晶格错配,从而促进薄
关键词:
0-FePt薄膜')" href="#">L10-FePt薄膜
有序化温度
垂直磁各向异性
磁交换耦合作用 相似文献
92.
Changjun Min Jinpeng Liu Ting Lei Guangyuan Si Zhenwei Xie Jiao Lin Luping Du Xiaocong Yuan 《Laser \u0026amp; Photonics Reviews》2016,10(6):978-985
Traditional detour‐phase hologram is a powerful optical device for manipulating phase and amplitude of light, but it is usually not sensitive to the polarization of light. By introducing the light‐metasurface interaction mechanism to the traditional detour phase hologram, we design a novel plasmonic nano‐slits assisted polarization selective detour phase meta‐hologram, which has attractive advantages of polarization multiplexing ability, broadband response, and ultra‐compact size. The meta‐hologram relies on the dislocations of plasmonic slits to achieve arbitrary phase distributions, showing strong polarization selectivity to incident light due to the plasmonic response of deep‐subwavelength slits. To verify its polarization sensitive and broadband responses, we experimentally demonstrate two holographic patterns of an optical vortex and an Airy beam at p‐ and s‐polarized light with wavelengths of 532nm, 633nm and 780nm, respectively. Furthermore, we realize an application example of the meta‐hologram as a polarization multiplexed photonic device for multi‐channel optical angular momentum (OAM) generation and detection. Such meta‐holograms could find widespread applications in photonics, such as chip‐level beam shaping and high‐capacity OAM communication.
93.
本文主要研究了调制探测激光场中铯Rydberg 原子阶梯型三能级系统的电磁感应透明(EIT) 效应. 铯原子基态6S1/2, 第一激发态6P3/2 和Rydberg 态形成阶梯型三能级系统, 探测光作用于6S1/2 (F = 4)→6P3/2(F' = 5) 的跃迁, 耦合光在Rydberg 跃迁线6P3/2→49S1/2 附近扫描, 形成Rydberg 原子EIT. 当对探测光频率施加一个几kHz 的调制时, 调制解调后的EIT 信号分裂为两个峰, 双峰间距与调制频率无关,而与调制幅度导致的失谐量大小(频率调制幅度) 成正比, 双峰间隔的一半等于探测光频率调制幅度的λp/λc = 1.67 倍. 实验结果与理论计算相一致. 本文的研究结果可应用于激光线型和频率抖动的实时监测. 相似文献
94.
基于带电粒子活化测谱方法在SGⅡ-U装置上开展了皮秒激光靶背鞘场机制质子加速实验研究,对靶参数进行了优化.利用带电粒子活化测谱方法测量了相同激光条件、不同Cu薄膜靶厚度情况下靶背鞘场加速质子的最高截止能量、角分布、总产额以及激光能量到质子的转化效率等关键参数.实验发现,SGⅡ-U皮秒激光靶背鞘场加速机制的最佳Cu薄膜靶厚度为10 μm,对应质子最高能量接近40 MeV,质子(>4 MeV)总产额约4×1012个,激光能量到质子的转化效率约2%.薄膜靶更厚或者更薄都会降低加速质子的最高截止能量;当靶厚减薄至1 μm时,皮秒激光的预脉冲开始对靶背鞘场产生显著影响,质子最高截止能量急剧下降,高能质子束斑呈现空心结构;而当靶厚增加至35 μm时,虽然质子束的能量有所降低,但是质子束斑的均匀性更好. 相似文献
95.
96.
97.
98.
By using of the invariant theory, we have studied the geometric phase of quantum dots in the time-dependent isotropic magnetic
field, the dynamical and geometric phases are given, respectively. 相似文献
99.
Min Wu Yan Lv Zhengping Fu Jiao Xu Ting Guo Yongxun Zhao 《Applied Surface Science》2010,256(23):7125-9486
The simultaneous Ag loaded and N-doped TiO2 hollow nanorod arrays with various contents of silver (Ag/N-THNAs) were successfully synthesized on glass substrates by one-pot liquid phase deposition (LPD) method using ZnO nanorod arrays as template. The catalysts were characterized by Raman spectrum, field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscope (HRTEM), ultraviolet-vis (UV-vis) absorption spectrum and X-ray photoelectron spectroscopy (XPS). The results suggest that AgNO3 additive in the precursor solutions not only can promote the anatase-to-rutile phase transition, but also influence the amount of N doping in the samples. The photocatalytic activity of all the samples was evaluated by photodegradation of methylene blue (MB) in aqueous solution. The sample exhibited the highest photocatalytic activity under UV light illumination when the AgNO3 concentration in the precursor solution was 0.03 M, due to Ag nanoparticles acting as electron sinks; When the AgNO3 concentration was 0.07 M, the sample performed best under visible light illumination, attributed to the synergetic effects of Ag loading, N doping, and the multiphase structure (anatase/rutile). 相似文献
100.
H.-L. Zhang S.-F. Wang R. Wang J. Jiao 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,73(4):489-493
The dislocation widths and Peierls stresses of glide dislocations and shuffle dislocations in graphene have been studied by
the improved Peierls-Nabarro (P-N) equation which contains the discrete correction. The discrete parameter is obtained from
a simple dynamic model in which the
interaction attributed to the variation of bond length and angle was considered. The restoring force in the improved P-N equation
is given by the gradient of the generalized stacking fault energy
surface (γ-surface). Our calculation shows that the widths of the shuffle dislocation and the glide dislocation are narrow
and the width of the shuffle dislocation is about twice wider than the glide dislocation. The Peierls stress of a shuffle
dislocation is one order of magnitude smaller than that of a glide dislocation. As a consequence, the shuffle dislocation
moves more easily than the glide dislocation. 相似文献