NSF: Magnetic Properties of Mesoscopic Multilayer Rings; 3D ferromagnetic ring device structures for spintronics.

这项研究的主要目的是探索3D多层结构和阵列的基本磁性、输运和集体性质。这种结构包括铁磁性多层膜(通常厚度为1-10 nm，由过渡金属和带有非磁性层作为间隔层的合金制成)，结构成直径为150 nm或更小的环。新的结构类别带来了重大的制造、表征和测量挑战，这些挑战远远超出了单个小组的专业知识，但我们在本提案中通过建立在剑桥和麻省理工学院小组之间先前在单层(2D)环上的成功合作来解决这一问题。这之前的合作已经在著名的期刊上发表了大量的文章，比如《物理》。莱茨牧师。两个小组之间的研究学生和博士后研究人员的交流非常富有成效，我们希望这将为新的合作提供非常强大的基础。具体地说，麻省理工学院小组将材料沉积和设备制造专业知识以及自旋电子学设备应用方面的专业知识带到该项目中，而剑桥小组则带来了磁性和光学测量以及磁性开关和动力学解释方面的专业知识。这使得一个非常强大的团队非常适合这个雄心勃勃的项目。我们还建议让几名学生和参与其中的博士后研究员参加两个机构之间的交流，以促进研究方案，并在国际范围内提供培训机会。我们的目标是创建一种新的基于多层环形结构的3D体系结构，既作为单一实体又作为阵列，以评估这种结构在设备和存储器应用中的潜力。

The main aim of the research is to explore the fundamental magnetic, transport and collective properties of 3D multilayer structures and arrays. Such structures consist of ferromagnetic multilayers (typically 1-10nm thickness, fabricated from transition metals and alloys with non-magnetic layers as spacers) structured into rings down to 150nm diameter or smaller. The new class of structures presents significant fabrication, characterisation and measurement challenges which go well beyond the expertise of a single group but which we address in this proposal by building on the previous successful collaboration on single layer (2D) rings between the Cambridge and MIT groups. This previous collaboration has produced numerous publications in prestigious journals such as Phys. Rev. Letts. and the exchange of research students and postdoctoral researchers between the two groups which have been very fruitful and we expect this to provide a very strong base for the new collaboration. Specifically, the MIT group bring materials deposition and device fabrication expertise and expertise in device applications in spintronics to the project while the Cambridge group bring expertise in magnetic and optical measurements and in the interpretation of magnetic switching and dynamics. Together this makes a very strong team well suited to this ambitious project. We also propose to have several students and the post doctoral researcher involved participate in exchanges between the two institutions both to facilitate the research programme and to provide a training opportunity in an international context. Our goal is to create a novel 3D architecture based on multilayer ring structures, both as single entities and as arrays, in order to assess the potential of such structures for device and memory applications.