MICROSCOPY Vol.45▶No.1 2010
â– Feature Articles: Research Articles by Selected Young Microscopists from East Asia

Current Progresses of Electron Energy-Loss Spectroscopy in National Taiwan University: Applications in Plasmonics and Surface Resonances in Nanomaterials

Ming-Wen Chu and Cheng Hsusan Chen

Scanning Transmission Electron Microscopy Laboratory, Center for Condensed Matter Sciences, National Taiwan University

Abstract: The scanning transmission electron microscopy (STEM) laboratory in National Taiwan University represents the first dedicated electron energy-loss spectroscopy (EELS) group in Taiwan. Our major expenditure in the past five years has been the development of the conjunction of STEM and EELS, STEM-EELS, enabling an electronic characterization at nanometer-scale spatial resolution. Using this combined technique of STEM-EELS, we have unraveled the intriguing surface-plasmon properties in individual gold nanoparticles, popularly known as plasmonics, and revived a class of surface resonances, surface exciton polaritons that had been largely ignored in the past. As what we will discuss through this article, STEM-EELS is not only an indispensable tool for nano-characterizations, but also an avenue for unexpected physics.