NIRT: Interfacial Forces in Active Nanodevices

这项提案是对NSF 06-595 NIRT类主动纳米结构和纳米系统倡议的回应。随着器件尺寸向分子尺度缩小，界面作用力变得越来越重要，传统的抹黑原子结构的理论变得不再适用。研究团队将结合新的实验和理论方法来确定传统理论的局限性，识别新的界面现象，开发纳米尺度的界面力的通用模型，并探索有源纳米设备的新策略。对化学调制纳米线和纳米缝隙中的半月板上毛细管力的测量和模拟将探索表面张力、静态和动态接触角、接触角滞后以及光和电场对毛细管驱动的长度尺度的变化。对界面力的研究将提供有关电场引起的电荷分布变化的信息，以及界面上的力，这在电润湿中是重要的。提出的研究将提高我们在纳米尺度上对流体流动、毛细现象和驱动的基本理解。这些结果将直接与有源纳米器件的设计和优化相关，并有助于理解微电子机械系统中不必要的附着以及地下水和石油在小孔中的传输。学生将接受广泛的跨学科培训，使他们能够成为快速发展的纳米技术领域的领导者。作为研究的一部分开发的多尺度建模软件将通过与桑迪亚国家实验室的合作公开提供。推广活动将与当地项目协调，包括纳米结构材料教育推广中心和材料研究科学与工程中心、年度物理博览会、青年才华中心以及青年天文学和工程计划。

This proposal was received in response to the Active Nanostructures and Nanosystems initiative, NSF 06-595, category NIRT. As device dimensions shrink towards molecular scales, interfacial forces become increasingly important and traditional theories that smear out atomic structure become inadequate. The research team will combine new experimental and theoretical methods to determine the limits of traditional theories, identify new interfacial phenomena, develop general models for interfacial forces at the nanometer scale, and explore new strategies for active nanodevices. Measurements and simulations of capillary forces on chemically modulated nanowires and on menisci confined in nanometer gaps will probe changes with length scale in surface tension, static and dynamic contact angles, contact angle hysteresis, and capillary actuation by light and electric fields. Studies of interfacial forces will provide information about field-induced changes in the charge distribution and forces at interfaces that are important in electrowetting. The proposed research will improve our fundamental understanding of fluid flow, capillary phenomena and actuation at the nanometer scale. The results will be directly relevant to the design and optimization of active nanodevices, and aid understanding of unwanted adhesion in micro-electro-mechanical systems and of transport of ground water and oil in small pores. Students will receive a broad interdisciplinary training that will enable them to become leaders in the rapidly developing field of nanotechnology. Multiscale modeling software developed as part of the research will be made publicly available through a collaboration with Sandia National Laboratories. Outreach will be coordinated with local programs, including the Center for Educational Outreach and the Materials Research Science and Engineering Center on nanostructured materials, the annual Physics Fair, the Center for Talented Youth, and the Youth for Astronomy and Engineering Program.