NIRT: Nanoscale Shape Memory Actuators and Swimming Bugs - Theory, Computing, and MBE Synthesis

建议：DMS-0304326PI：Mitchell Luskin[luskin@mahy.umn.edu]机构：明尼苏达大学双城分校标题：NIRT：纳米级形状记忆执行器和游泳臭虫-理论、计算和MBE合成研究人员将开展一项研究计划，开发形状记忆和新兴的铁磁性形状记忆材料，用于在小范围内产生运动。这些材料自发地经历马氏体(无扩散的，结构的)相变和形状的变化。在铁磁形状记忆材料中，形状变化可以由远程施加的磁场触发。由于它们的单位体积输出功非常高，以及单晶薄膜中预计可能发生的异常大的形状变化，这些材料是纳米级马达的良好候选者。研究人员将开发纳米级马达的理论模型和计算预测，这些马达可以移动、放置、定向、驱动和推进。将启动分子束外延生长NiTi薄膜的计划，并将在NiTi和Ni2MnGa单晶薄膜上实现所预测的设计。这项研究包括对相变行为和小尺度形状记忆效应的基础理论/计算/实验研究，其基础是对一系列小尺寸样品中的马氏体相变的研究。新兴的多尺度数学方法，扩展到原子尺度，将在指导纳米致动器设计方面发挥关键作用。在纳米尺度上产生明确的物体运动是新兴纳米技术领域的关键组成部分。这为纳米机器人的发展奠定了基础，在光学设备以及传感器的放置和定位中发挥着关键作用，是促进物理世界和生物基本过程之间相互作用的设备的使能部件。在小尺度上产生明确定义的运动和力尤其受到这些尺度上界面力和粘性力的支配以及随机布朗运动的不稳定效应的阻碍。研究人员提出的用于这些尺度的形状记忆材料有望克服这些障碍，实现清晰的小尺度运动。作为几个新兴领域的基础技术，这项研究直接支持美国在材料科学、纳米技术和国家安全方面的战略目标。

Proposal: DMS-0304326PI: Mitchell Luskin [luskin@mathy.umn.edu]Institution: University of Minnesota - Twin CitiesTitle: NIRT: Nanoscale Shape Memory Actuators and Swimming Bugs - Theory, Computing, and MBE SynthesisABSTRACTThe investigators will undertake a program of research on the development of shape memory and emerging ferromagnetic shape memory materials for the production of motion at small scales. These materials spontaneously undergo a martensitic (diffusionless, structural) phase transformation with a change of shape. In the ferromagnetic shape memory materials, the shape change can be triggered by a remotely applied magnetic field. Because of their exceptionally high work output per unit volume, and the unusually large shape changes that are predicted to be possible in single crystal thin films, these materials are good candidates for nanoscale motors. The investigators will develop theoretical models and computational predictions for nanoscale motors that move, place, orient, actuate, and propel. A program of molecular beam epitaxial growth of NiTi films will be initiated, and the predicted designs will be put into practice on single crystal thin films of NiTi and Ni2MnGa. The research includes a fundamental theoretical/ computational/ experimental study of the behavior of phase transformation and the shape memory effect at small scales, resting on the study of the martensitic phase transformation in a sequence of specimens of smaller and smaller size. Emerging multiscale mathematical methods, expanded to atomic scale, will play a key role in guiding nanoactuator design.The production of well defined movements of objects at the nanoscale is a critical component of the emerging field of nanotechnology. This underlies the development of nanorobots, plays a crucial role in optical devices and the placement and orientation of sensors, and is an enabling component of devices that foster the interaction between the physical world and the fundamental processes of biology. The production of well defined motions and forces at small scales is particularly hampered by the dominance of interfacial and viscous forces at these scales and the destabilizing effects of random Brownian motions. The shape memory materials proposed by the investigators for use at these scales promise to overcome these impediments to well defined small-scale motion. As an underlying technology for several emerging fields, the research directly supports US strategic goals in materials science, nanotechnology, and national security.