阳极氧化铝模板表面自组织条纹的形成

对未经化学抛光处理的Al进行阳极氧化得到阳极氧化铝模板，发现Al表面形成了条纹与多孔阵列共存的自组织结构，用原子力显微镜对这种结构进行了研究.借助Brusselator模型对条纹的形成机理进行了讨论，认为条纹图案是Al表面氧化层/电解液界面的Al₂O₃在整个反应过程中的生成和溶解两个过程相互竞争导致的，只有在特定的反应条件才会出现高度有序的结构.  

并五苯分子在Ag(110)表面成膜过程中的结构研究

采用低能电子衍射原位研究了并五苯分子（C₂₂H₁₄）在Ag(110)单晶表面的生长，观察了在初期沉积过程及随后基底变温过程中分子层结构的形成和变化.室温下并五苯分子在Ag(110)基底表面具有高的迁移性，从开始无序的亚单层膜结构逐渐形成有序的单层膜结构．实验和理论分析表明：并五苯分子平铺在Ag(110)表面，形成了与基底构成有关的有序结构，存在沿基底晶向成镜面对称的两种畴界取向，在基底温度从室温升高到接近并五苯升华温度的过程中，基底上的有序分子层结构保持稳定不变  

扫描隧道显微镜纳米云纹法的实验研究

提出了应用扫描隧道显微镜(STM)纳米云纹法测量面内位移的原理。测量中,把扫描隧道显微镜的探针扫描线作为参考栅,把物质原子晶格栅结构作为试件栅,对这两组栅线干涉形成的云纹进行了纳米级变形测量。对扫描隧道显微镜纳米云纹的形成原理及测量方法进行了详尽的讨论,并运用该方法对高定向裂解石墨(HOPG)的纳米级变形虚应变进行了测量研究,得到了随扫描范围变化的虚应变场,并与理论值进行了比较。  

扫描探针显微学中的云纹方法

在扫描探针显微镜（SPM）的扫描过程中，由SPM的扫描线与物质表面周期性晶格结构进行干 涉可以形成纳米云纹图像.采用高取向热解石墨（HOPG）和云母作为试件，分别对扫描隧道 显微镜（STM）和原子力显微镜（AFM）云纹进行了研究，实验结果与理论分析完全一致.SPM 纳米云纹法在纳米测量和表征方面具有较大的应用前景.  

扫描隧道显微镜分辨能力的研究:对Si(111)-(7×7)表面的观察

用超高真空扫描隧道显微镜首次同时清晰地分辨出Si(111) (7×7)表面每个元胞中的 12个顶戴原子和 6个静止原子,这 6个静止原子的亮度与无层错半元胞内中心顶戴原子的亮度基本相同. 第一性原理计算图像和STM实验结果完全符合,针尖的尺度小于 7 时,可以完全同时分辨出Si(111) (7×7)表面的静止原子.  

Formation and local electronic structure of Ge clusters on Si(111)-7×7 surfaces

We report the formation and local electronic structure of Ge clusters on the Si（111）-7×7 surface studied by using variable temperature scanning tunnelling microscopy （VT-STM） and low-temperature scanning tunnelling spectroscopy （STS）. Atom-resolved STM images reveal that the Ce atoms are prone to forming clusters with 1.0 nm in diameter for coverage up to 0.12 ML. Such Ce clusters preferentially nucleate at the centre of the faulted-half unit cells, leading to the ＇dark sites＇ of Si centre adatoms from the surrounding three unfaulted-half unit cells in filled-state images. Biasdependent STM images show the charge transfer from the neighbouring Si adatoms to Ce clusters. Low-temperature STS of the Ce clusters reveals that there is a band gap on the Ce cluster and the large voltage threshold is about 0.9 V.  

数字纳米云纹法的实验研究

提出了一种新的测量物质纳米级变形的云纹方法———数字纳米云纹法,在测量过程中,借助于各种电镜,采用具有周期结构的晶体物质的晶格或一些过渡金属、贵金属材料规则的表面原子重构作为试件栅。该试件栅的节距可达到亚纳米的量级,使得该方法可以在纳观范围内测量物体的面内位移,应变。参考栅采用计算机绘制的正弦型数字栅。详细地论述了该数字栅的制作方法,数字纳米云纹条纹的形成机理,及位移、应变的测量方法,云纹条纹的相移方法和倍增方法。  

The influence of annealing temperature on the morphology of graphene islands

We report on temperature-programmed growth of graphene islands on Ru(0001) at annealing temperatures of 700°C,800°C,and 900°C.The sizes of the islands each show a nonlinear increase with the annealing temperature.In 700°C and 800°C annealings,the islands have nearly the same sizes and their ascending edges are embedded in the upper steps of the ruthenium substrate,which is in accordance with the etching growth mode.In 900°C annealing,the islands are much larger and of lower quality,which represents the early stage of Smoluchowski ripening.A longer time annealing at 900°C brings the islands to final equilibrium with an ordered moir’e pattern.Our work provides new details about graphene early growth stages that could facilitate the better control of such a growth to obtain graphene with ideal size and high quality.  

Measuring thermoelectric property of nano-heterostructure

A method of measuring the thermoelectric power of nano-heterostructures based on four-probe scanning tunneling microscopy is presented. The process is composed of the it in-situ fabrication of a tungsten-indium tip, the precise control of the tip-sample contact and the identification of thermoelectric potential. When the temperature of the substrate is elevated, while that of the tip is kept at room temperature, a thermoelectric potential occurs and can be detected by a current-voltage measurement. As an example of its application, the method is demonstrated to be effective to measure the thermoelectric power in several systems. A Seebeck coefficient of tens of μV/K is obtained in graphene epitaxially grown on Ru (0001) substrate and the thermoelectric potential polarity of this system is found to be the reverse of that of bare Ru (0001) substrate.  

Manipulation and control of a single molecular rotor on Au(111) surface

Three different methods are used to manipulate and control phthalocyanine based single molecular rotors on Au (111) surface: (1) changing the molecular structure to alter the rotation potential; (2) using the tunnelling current of the scanning tunnelling microscope (STM) to change the thermal equilibrium of the molecular rotor; (3) artificial manipulation of the molecular rotor to switch the rotation on or off by an STM tip. Furthermore, a molecular ’gear wheel’ is successfully achieved with two neighbouring molecules.