Ultrafast Nonlinear Microscopy in Nanorods and Nanostructured Networks

在这个由化学学部实验物理化学项目资助的项目中，北卡罗来纳大学教堂山分校的John M. Papanikolas教授将结合泵浦探针方法和非线性显微镜来研究一维纳米结构、网络和纳米器件在超快时间尺度上的载流子动力学。该项目的目标是阐明载体动力学和物体局部形状之间的关系，这是理解纳米科学和纳米技术中许多问题的根本重要和关键的问题。从结构到结构的行为变化，甚至在同一结构内不同空间位置之间的行为变化，是复杂性的标志，它的存在对那些希望在各种设备应用中开发纳米级材料的人提出了重大挑战。该项目将开发一种新的显微镜技术，在从飞秒到纳秒的时间尺度上，激发一个空间位置的纳米结构，探测另一个空间位置的动力学。Papanikolas教授和他的学生将使用这种空间分离的泵探针显微镜来可视化电荷载流子通过单个纳米棒和网络的迁移。这个项目将有助于我们对复杂纳米系统的理解，同时在研究项目的背景下促进教学、培训和学习。研究对象包括研究生、本科生和高中生。他们将开发技术先进的仪器，将这些方法应用于单纳米结构的研究，参与研究结果的交流，并参与为中学生开展的突出其研究的活动。

In this project, funded by the Experimental Physical Chemistry Program of the Chemistry Division, Prof. John M. Papanikolas of the University of North Carolina at Chapel Hill will combine pump-probe methodologies with nonlinear microscopy to investigate the charge carrier dynamics in one-dimensional nanostructures, networks and nanodevices on ultrafast time scales. The goal of the project is to elucidate the relation between the carrier dynamics and the local shape of the object, an issue that is fundamentally important and critical to understanding many problems in nanoscience and nanotechnology. Variation in behavior from structure-to-structure, and even between different spatial locations within the same structure, is a hallmark of complexity and its presence poses a major challenge to those wishing to exploit nanoscale materials in a variety of device applications. The project will develop a new microscopy technique that will excite a nanostructure in one spatial location and probe the dynamics in another, on time scales ranging from femtoseconds to nanoseconds. Professor Papanikolas and his students will use this spatially-separated pump-probe microscope to visualize charge carrier migration through individual nanorods and networks. This project will contribute to our understanding of complex nanosystems while promoting teaching, training, and learning in the context of a research program. Graduate, undergraduate and high school students will participate in this research. They will develop the technologically sophisticated instrumentation, apply those methods to the study of single nanostructures, take part in the communication of their results, and participate in the development of activities for middle school students that highlight their research.