NER: Using Surface Interactions and Continuum Models to Develop New Modes of Nano-Device Operation

四个探索性的纳米级器件，利用表面相互作用的突出显示在这个建议。 第一种方法是利用晶格配准来制作具有可调旋转和平移运动的纳米器件。 其他人使用由表面粘附和原子尺度注册引起的纳米管的双稳态（管/带）来开发具有独特机械性能的纳米泵，虎钳，开关和互连网络。 为了确定这些设备的可行性，必须开发新的多尺度建模技术。 这些模型必须包含从量子力学到结构的各个层次的重要物理学。 PI的综合专业领域涵盖了整个范围，使他们能够仔细决定在每个尺度上必须包括哪些物理学以及可以忽略哪些物理学。 Crespi博士新开发的原子尺度注册表和表面相互作用的潜力将被整合到Mockensturm博士使用所谓的Cosserat连续介质力学开发的非线性结构理论中。 这些设备的理论研究是困难的，计算昂贵的分子动力学成为可行的连续模型。 无论这些推测性器件最终能否成功，所开发的新建模技术都将为进一步的器件发现提供基础。随着尺寸减小到原子尺度，表面相互作用扮演着更重要的角色，以至于它们可以诱导新颖的和宏观上奇特的行为。 在纳米结构的最终极限，基本上每个原子都可能位于表面，特别是在可以具有二维晶体结构（石墨，而不是金刚石）的碳基纳米结构中。 因此，长程表面相互作用是纳米尺度器件的基本机制，在宏观世界中很少重要，通常被忽视。 在纳米尺度上，货车德瓦耳斯相互作用使设备的行为就像它们被涂上了一层厚厚的糖蜜。 这些表面相互作用使碳纳米管具有两种稳定状态。 最常见的状态是管状。 然而，所谓的纳米带只是纳米管的另一种稳定（塌陷）状态。 在这项研究中，研究人员将利用这种双稳态行为来开发纳米器件操作的新模式。 具体而言，纳米泵，虎钳，开关和互连网络具有独特的机械性能的可行性将进行研究。

Four exploratory nano-scale devices that take advantage of surface interactions are highlighted in this proposal. The first uses lattice registry to make nano-devices featuring tunable rotary and translational motion. The others use the bistability (tube/ribbon) of nanotubes caused by surface adhesion and atomic-scale registry to develop nano-pumps, vices, switches, and interconnected networks with unique mechanical properties. To determine the feasibility of these devices, new multi-scale modeling techniques must be developed. These models must incorporate the important physics at every level from quantum mechanical to structural. The combined areas of expertise of the PIs covers this full range, allowing them to carefully decide what physics must be included and what can be neglected at each scale. Dr. Crespi's newly developed potential for atomic-scale registry and surface interaction will be integrated into the nonlinear structural theories developed by Dr. Mockensturm using so-called Cosserat continuum mechanics. Theoretical studies of these devices which are difficult and computationally expensive using molecular dynamics become feasible using continuum models. Regardless of the ultimate success of these speculative devices, the new modeling techniques developed will provide a foundation for further device discovery.As sizes decrease to the atomic scale, surface interactions take on a more important role, to the point where they can induce novel and macroscopically peculiar behaviors. At the ultimate limit of a nanostructure, it is possible for essentially every atom to be at the surface, particularly in carbon-based nanostructures which can have a two dimensional crystalline structure (graphite, not diamond). Long-range surface interactions are, thus, a fundamental mechanism in nano-scale devices that are rarely important in the macroscopic world and typically ignored. At the nano-scale, van der Waals' interactions make devices behave as if they are coated with a thick layer of molasses. These surface interactions allow carbon nanotubes to have two stable states. The most commonly seen state is tubular. However, a so-called nano-ribbon is just another stable (collapsed) state of nanotubes. In this research the investigators will use this bi-stable behavior to develop new modes of nano-device operation. Specifically, the feasibility of nano-pumps, vices, switches, and interconnected networks with unique mechanical properties will be studied.