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Electrical, Optical and Ionic Probe inside Transmission Electron Microscope Xuedong Bai1, Zhi Xu1, Peng Gao1, Kaihui Liu1, Wenlong Wang1 and Enge Wang2 1 Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China 2 School of Physics, Peking University, Beijing 100871, China ABSTRACT In-situ transmission electron microscopy (TEM) method is powerful in a way that it can directly correlate the atomic-scale structure with physical and chemical properties. We will report on the construction and applications of the homemade in-situ TEM electrical and optical holders. Electrical transport of carbon nanotubes and photoconducting response on bending of individual ZnO nanowires have been studied inside TEM. Oxygen vacancy electromigration and its induced resistance switching effect have been probed in CeO2 films. INTRODUCTION It is known that the properties of nanomaterials depend strongly on their structure, size and chemical composition. To maintain and utilize the basic and technological advantages offered by the size specificity and selectivity of nanostructures, it is significant to characterize the properties of an individual nanostructure with well-defined structure. Characterizing the properties of individual nanostructures is still a challenge to many existing testing and measuring techniques because of their small size, which constrains the well-established testing techniques. And the small size of nanostructures also makes their manipulation rather difficult. Thus the new methods and methodologies must be developed to quantify the properties of individual nanostructures. In recent several years, one kind of special transmission electron microscopy (TEM) specimen stage with the function of scanning tunnelling microscopy (STM) was developed [1-3]. This in situ TEM method not only can provide the properties of an individual nanostructure, but also can give the microstructure through TEM analysis. It is an ideal technique for understanding the property-structure relationship of the nanostructures. This paper reviews our recent progress in using in situ TEM technique for probing electrical and optical properties of carbon nanotubes [4, 5], photoconducting response on bending of individual ZnO nanowires [6], and oxygen ion (vacancy) electromigration and its induced resistance switching effect of CeO2 films [7. 8].

EXPERIMENTAL TEM is a conventional tool for characterizing the atomic level structures of solid state materials. A novel and unique approach can be developed by integrating the structural information of a nanostructure provided by TEM with the properties measured in situ from the same nanostructure. We have built a STM mechanical unit integrated with a commercial TEM. The STM unit is responsible for manipulation and property measurements of individual

nanostructures. The structural information and physical phenomenon can be observed in situ TEM. In our studies, the design the STM tip holder has four legs that embrace the sapphire ball. The coarse movement of the tip in the direction perpendicul