**High-Resolution Near-Field Optical Microscopy: A Sub-10 Nanometer Probe for Surface Electromagnetic Field and Local Dielectric Trait**

Jen-You Chu1 and Juen-Kai Wang2,3

*1Material and Chemical Research Laboratories Industrial Technology Research Institute, Hsinchu 2Center for Condensed Matter Sciences, National Taiwan University, Taipei 3Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei Taiwan* 
