Development of a Dual-Probe Scanning Tunneling Microscope for Investigating Nanoscale Materials and Devices

9522221博兰该奖项为开发双探头扫描隧道显微镜(DP-STM)提供资金，以研究纳米材料和器件的性能。DP-STM基本上与传统的单探头STM相同，只是它允许两个独立的STM探头彼此相距10-100 nm。这一能力将通过在每个STM探针上控制生长纳米晶须来实现。描述了一种将胡须探针可靠地定位在规定间隔内的方法。与传统的STM只能测量材料的局部静态性质不同，DP-STM开辟了一个全新的研究领域，特别是在非局部动力学和松弛现象方面。通过选择STM探头的位置，可以测量材料中沿任何特定方向的输运和表面带散。各种新颖的泵浦-探测实验也是可能的。例如，可以测量特定位置的电荷注入如何影响附近某个位置的静电势和态密度。后者特别有趣，因为它相当于对局部化学反应的基本描述。DP-STM也代表了一种潜在的强有力的技术来探测纳米器件的特征和性能。***

9522221 Boland This award provides funds to develop a dual-probe scanning tunneling microscope (DP-STM) to investigate nanoscale material and device properties. DP-STM is essentially identical to conventional single probe STM except that it enables two independent STM probes to be positioned 10-100nm from each other. This capability will be achieved by the controlled growth of nanowhiskers on each STM probe. A method is described to reliably position the whiskered probes within the prescribed separation. In contrast to conventional STM which can only measure local static properties of materials, DP-STM opens up whole new areas of investigation, particularly in the area of non-local dynamical and relaxation phenomena. By selecting the locations of the STM probes it is possible to measure transport and surface band dispersion along any particular direction in the material. A variety of novel pump- probe experiments are also possible. For instance, it is possible to measure how charge injection at a particular location affects the electrostatic potential and density of states at some nearby location. The latter is particularly interesting since it amounts to a fundamental description of the local chemical reactivity. DP-STM also represents a potentially powerfully technique to probe the characteristics and performance of nanodevices. ***