Scanning Probe Microscopy for fundamental studies in nanoscience

原子力显微镜（AFM）是纳米科学的理想工具，因为它允许成像，操纵和表征单个纳米尺寸的物体。我的研究计划的长期目标是通过建立在最近的NSERC DG资助的实验突破和仪器开发，继续获得关于信息存储或处理的纳米级系统的结构-性质关系的基本了解。该研究计划为HQP的培训和许多潜在的社会经济技术副产品提供了丰富的，跨学科的和世界一流的环境。 我们正计划了解电导和单分子器件的机械性能，这些器件可以使用我们两个独特的UHV AFM系统形成未来纳米电子学的基础。我们想了解分子电子学中的问题：接触的作用。目前可用的实验数据与理论建模的比较是非常困难的，因为接触引线的原子结构是最重要的，但通常不受实验控制。 另一个项目是了解有机分子系统中的有序和缺陷如何决定电导率和光电特性。通过用~100 fs的光脉冲泵浦样品，我们将产生激子并最终产生自由电荷。通过检测AFM针尖上产生的静电力，我们将实现纳米尺度的空间分辨率。通过与光学和太赫兹光谱学专家合作，我们将深入了解有机系统中的光物质相互作用、电荷分离和导电性。 我们计划使用我们的低温原子力显微镜来表征半导体和金属量子点（QD）的充电。我们对机械检测的单电子信号的详细定量理解使我们能够提取单个和耦合QD的能级，态密度以及耦合强度。我们将测试一个令人兴奋的理论预测，即相干时间T1可以直接从我们的AFM耗散测量中提取！我们还旨在观察由于单个分子耦合到量子点的电荷转移，导致实验上可观察到的能级和能级对准的移位。通过改变耦合化学，这将导致对有机接触的详细理解。 最后，我们将继续努力从根本上了解生物系统如何处理信息。我们特别感兴趣的是了解是什么决定了神经元的信号处理能力。我们最近证明，我们可以构建新的功能性神经元连接。因此，我们现在可以通过实验控制所有相关参数，以了解一个简单的生物神经元网络，以期在工程纳米电子系统中吸取经验教训。

The atomic force microscope (AFM) is an ideal tool for Nanoscience, as it allows imaging, manipulation and characterization of individual nanometer sized objects. The long-term aim of my research program is to continue to gain a fundamental understanding of the structure-property relation of nanoscale systems with respect to information storage or processing by building on recent NSERC DG funded experimental breakthroughs and instrumentation developments. This research program provides a rich, interdisciplinary and world-class environment for the training of HQP and many potential socio-economic technology spin-offs. We are planning on understanding the conductance and the mechanical properties of single molecular devices that could form the basis of future nanoelectronics using our two unique UHV AFM systems. We want to understand THE issue in molecular electronics: the role of contacts. The comparison of currently available experimental data with theoretical modeling is very difficult, as the atomic structure of the contact leads is of utmost importance, but usually not experimentally controlled. A further project is to understand how order and defects in organic molecular systems determines conductivity and opto-electronic properties. By pumping the sample with ~100 fs optical pulses we will generate excitons and ultimately free charges. By detecting the resulting electrostatic forces on the AFM tip we will achieve nm scale spatial resolution. In collaboration with specialists in optical and THz spectroscopy we will thus gain a deep understanding of light-matter interactions, charge separation and conductivity in organic systems. We plan to use our cryogenic AFM to characterize the charging of semi-conducting and metallic quantum dots (QD). Our detailed quantitative understanding of the mechanically detected single electron signals allows us to extract the energy levels, density of states as well as coupling strengths of individual and coupled QD. We will test an exciting theoretical prediction that the coherence time T1 can be directly extracted from our AFM dissipation measurement! We also aim to observe the charge transfer due to a single molecule coupled to a QD, resulting in a shift of the experimentally observable energy levels and energy level alignment. By changing the coupling chemistry this will lead to a detailed understanding of organic contacts. Finally, we will continue our efforts to fundamentally understand how biological systems process information. We are in particular interested in understanding what determines the signal processing capabilities in neurons. We recently demonstrated that we could construct new, functioning neuronal connections. We can thus now experimentally control all the relevant parameters to understand a simple biological neuronal network with a view of implementing the lessons learned in engineered nanoelectronics systems.