共查询到20条相似文献,搜索用时 672 毫秒
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《电子元件与材料》2016,(9):33-36
采用电化学沉积法封装阳极氧化铝(AAO)模板,制备出不同直径的Fe纳米线阵列。Fe纳米线阵列的形貌、组成、晶型、磁学性能分别通过场发射扫描电子显微镜(SEM)、X-射线能谱仪(EDS)、X-射线衍射仪(XRD)、震动样品磁强计(VSM)进行表征。结果表明:电化学沉积法可以制备出直径为33~95 nm的Fe纳米线;纳米线排列有序,粗细均匀,具有明显的[110]择优取向。VSM测试结果表明纳米线的直径对其磁性能影响很大。当纳米线直径为33~40 nm时,纳米线具有明显的磁各向异性,垂直模板表面的方向为易磁化方向,该方向上矫顽力达112 745.4 A/m以上,矩形比达0.43以上;当纳米纤维直径为75~95 nm时,纳米线的磁各向异性较弱,轴向上矫顽力和矩形比也较小。 相似文献
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近年来,一维纳米材料如纳米管、纳米线、纳米棒等由于在纳米电子器件和光电子器件中的潜在应用前景而吸引了众多科研小组的兴趣。ZnO纳米材料作为一种宽带系半导体,因其可以在各种高科技产品中的应用如光催化剂、气敏元件、光电二极管、变电阻等已引起人们广泛的研究,到现在为止,许多方法用来制备一维ZnO纳米材料,如电弧法、化学气相沉积、模板法和电化学沉积等。本文用溶液法合成ZnO纳米棒,并对其进行电子显微学的观察与表征。 相似文献
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稀磁半导体(DMS)是一种新型功能材料,其结合了半导体和磁性材料的电学和磁学性质,具有优异的磁、磁光和磁电等性能,在未来的光电器件、自旋电子器件和计算机等领域具有广阔的开发应用前景。简述了我国稀磁半导体的研究成果及进展,重点讨论了稀磁半导体的制备合成方法,分析了各种制备方法的优缺点,包括分子束外延技术(MBE)、离子注入法、脉冲激光沉积(PLD)、助熔剂法、化学气相沉积(CVD)、溶胶-凝胶和水热法等。同时分析了目前稀磁半导体遇到的问题和困难,探讨了其解决方法,展望了稀磁半导体潜在的应用前景。 相似文献
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高矫顽力和高剩磁比的Ni-Pt多层纳米线 总被引:1,自引:0,他引:1
信息科学的迅猛发展使得人们追求更高的存储密度和更小的存储点。因此发展高密度磁存储记录介质以及相应的新存储技术的研究是目前的研究热点之一。我们设计了一种铁磁性金属和非铁磁性金属交替的纳米线阵列来替代单一铁磁性纳米线阵列。每个铁磁层都可看作是一个单磁畴铁磁性纳米粒子,因此该结构不但高度有序,且还保持了铁磁性纳米粒子的高矫顽力特性。我们利用脉冲电化学沉积法在多孔阳极氧化铝(AAO)模板纳米线孔道中成功制备了Ni-Pt多层纳米线。 相似文献
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The texture of electro-deposited iron foils was measured. It was observed that a {110} fibre texture developed in these deposited
iron foils. When a sufficiently strong magnetic field was applied along the deposit layer during the deposition process, a
{110}〈001〉 texture developed from the initially formed {110} fibre texture, with the 〈001〉 axis parallel to the magnetic field.
An attempt has been made to explain the texture development and the effect of the applied magnetic field in the deposition
process. 相似文献
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Directed Self‐Assembly as a Route to Ferromagnetic and Superparamagnetic Nanoparticle Arrays
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Laura T. Schelhas Richard A. Farrell Udayabagya Halim Sarah H. Tolbert 《Advanced functional materials》2014,24(44):6956-6962
Block co‐polymer patterns are attractive candidates for nanoparticle assemblies. Directed self‐assembly of block co‐polymers in particular allows for long range ordering of the patterns, making them interesting scaffolds for the organization of magnetic particles. Here, a method to tune the channel width of polymer‐derived trenches via atomic layer deposition (ALD) of alumina is reported. The alumnia coating provides a much more thermally robust pattern that is stable up to 250 °C. Using these patterns, magnetic coupling in both ferromagnetic and superparamagnetic nanocrystal chains is achieved. 相似文献
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Xingsen Gao Lifeng Liu Balaji Birajdar Michael Ziese Woo Lee Marin Alexe Dietrich Hesse 《Advanced functional materials》2009,19(21):3450-3455
A novel nanopatterning method using pulsed laser deposition through an ultrathin anodic aluminium oxide (AAO) membrane mask is proposed to synthesize well‐ordered nanodot arrays of magnetic CoFe2O4 that feature a wide range of applications like sensors, drug delivery, and data storage. This technique allows the adjustment of the array dimension from ~35 to ~300 nm in diameter and ~65 to ~500 nm in inter‐dot distance. The dot density can be as high as 0.21 Terabit in.?2. The microstructure of the nanodots is characterized by SEM, TEM, and XRD and their magnetic properties are confirmed by well‐defined magnetic force microscopy contrasts and by hysteresis loops recorded by a superconducting quantum interference device. Moreover, the high stability of the AAO mask enables the epitaxial growth of nanodots at a temperature as high as 550 °C. The epitaxial dots demonstrate unique complex magnetic domains such as bubble and stripe domains, which are switchable by external magnetic fields. This patterning method creates opportunities for studying novel physics in oxide nanomagnets and may find applications in spintronic devices. 相似文献
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为了定量地得到磁场梯度对a-Si∶H薄膜沉积速率的影响,对单磁场线圈分散场MWECR CVD系统等离子体室和沉积室中用三种方法得到的磁场形貌进行了研究.通过洛伦兹拟合的方法定量地得到了这些磁场形貌的磁场梯度.结果表明,样品台下面放置钐钴永磁体并使磁场线圈电流为137.7A时其衬底附近磁场梯度值最大,样品台下面无钐钴永磁时,磁场线圈电流分别为137.7A和115.2A的磁场梯度值依次为次之和最小.制备a-Si∶H薄膜时,在衬底附近具有高的磁场梯度值可以得到高的沉积速率.通过红外吸收谱技术分析,虽然样品台下面放置钐钴永磁体并使磁场线圈电流为137.7A下能得到最大的沉积速率,但是沿样品台半径方向沉积速率呈现很明显的不均匀分布. 相似文献
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Jeroen H. Franken Mark A. J. van der Heijden Tim H. Ellis Reinoud Lavrijsen Carsten Daniels Damien McGrouther Henk J. M. Swagten Bert Koopmans 《Advanced functional materials》2014,24(23):3508-3514
Focused‐electron‐beam‐induced deposition (FEBID) is employed to create freestanding magnetic nanostructures. By growing Fe nanopillars on top of a perpendicular magnetic domain wall (DW) conduit, pinning of the DWs is observed due to the stray fields emanating from the nanopillar. Furthermore, a different DW pinning behavior is observed between the up and down magnetic states of the pillar, allowing to deduce the switching fields of the pillar in a novel way. The implications of these results are two‐fold: not only can 3‐dimensional nano‐objects be used to control DW motion in applications, it is also proposed that DW motion is a unique tool to probe the magnetic properties of nano‐objects. 相似文献
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Kai Schlage Lars Bocklage Denise Erb Jade Comfort Hans‐Christian Wille Ralf Röhlsberger 《Advanced functional materials》2016,26(41):7423-7430
Magnetoelectronic multilayer devices are widely used in today's information and sensor technology. Their functionality, however, is limited by the inherent properties of magnetic exchange or dipolar coupling which constrain possible spin configurations to collinear or perpendicular alignments of adjacent layers. Here, a deposition procedure is introduced that allows for a new class of layered materials in which complex spin structures can be accurately designed to result in a multitude of new and precisely adjustable spintronic and magnetoresistive properties. The magnetization direction and coercivity of each individual layer are determined by the deposition process in oblique incidence geometry and can be completely decoupled from neighboring layers. This applies for layers of any ferromagnetic material down to layer thicknesses of a few nm and lateral dimensions of a few 100 nm, enabling the design of efficient and compact magnetoelectronic devices, encompassing precision magnetoresistive sensors as well as layer systems with multiple addressable remanent states for magnetic memory applications. 相似文献
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在当今信息社会时代,需要存储的信息总量正在急剧增加。与光存储技术和半导体存储技术相比而言,磁记录技术占领着几乎90%的存储市场。磁力显微镜( magnetic force microscope,MFM)的发展与磁记录工业密切相关。然而,从1987年至今,MFM的分辨率仍然停留在50~10 nm的水平,传统思路已经很难再实现突破。本论文基于MFM探针的窄带-频率调制机理,发展接近表面磁力显微镜方法,实现对纳米结构中磁畴状态的超高分辨率成像。该工作的关键在于合理利用MFM探针的窄带-频率调制机理,优化设计动态信号处理模块,精确控制探针-样品间距(5 nm 以下),独立分离磁力像和表面像(磁力像为交流信号,原子力像为直流信号),由此测量和解释纳米尺度磁畴结构。该方面的工作对于纳米磁畴结构的设计、核心磁性器件的研究起到非常关键的作用,为下一代磁记录技术的发展提供了新型的有力工具。 相似文献
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为了提高谐变磁偶极子辐射磁矩的测试精度,避免测量角度对磁矩测量结果的影响,提出利用三分量磁通门传感器通过在空间多点测量磁场强度来获得磁偶极子辐射磁矩的新方法,与传统的两点法相比,该方法可以在任意角度下实现对辐射源辐射磁矩的测量,而不需要事先确定角度信息,且提高了磁矩的测量精度. 相似文献
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通过电子束诱导沉积的方法制备了钴(Co)微米线,并利用扫描电子显微镜(SEM)、原子力/磁力显微镜(AFM/MFM)以及物性测量系统(PPMS)等手段对Co微米线的沉积尺寸、微结构、铁磁性和电学性质进行了测试和分析。研究结果表明:Co微米线轮廓清晰、均匀性好。在不同的沉积条件下,微米线的实际长度与设定长度基本一致;实际宽度数据呈类梯形分布,半高宽是设定值的2~10倍;实际厚度低于设定厚度的60%。沉积电流对Co微米线的铁磁特性有重要影响。当沉积电流大于0.5 nA时,样品呈现出良好的铁磁特性。另外,电学性能测试结果显示Co微米线呈现绝缘特性。成功制备了室温铁磁绝缘Co微米线,这将有助于深入开展微纳尺度的结构与器件的研究和应用。 相似文献