%A Mai Takase,Satoshi Yasuda,Kei Murakoshi %T Single-site surface-enhanced Raman scattering beyond spectroscopy %0 Journal Article %D 2016 %J Front. Phys. %J Frontiers of Physics %@ 2095-0462 %R 10.1007/s11467-015-0490-0 %P 117803-${article.jieShuYe} %V 11 %N 2 %U {https://journal.hep.com.cn/fop/EN/10.1007/s11467-015-0490-0 %8 2016-04-29 %X

Recent progress in the observation of surface-enhanced Raman scattering (SERS) is reviewed to examine the possibility of finding a novel route for the effective photoexcitation of materials. The importance of well-controlled SERS experiments on a single molecule at a single site is discussed based on the difference in the information obtained from ensemble SERS measurements using multiple active sites with an uncontrolled number of molecules. A single-molecule SERS observation performed at a mechanically controllable breaking junction with a simultaneous conductivity measurement provides clear evidence of the drastic changes both in the intensity and in the Raman mode selectivity of the electromagnetic field generated by localized surface plasmon resonance. Careful control of the field at a few-nanometer-wide gap of a metal nanodimer results in the modification of the selection rule of electronic excitation of an isolated single-walled carbon nanotube. The examples shown in this review suggest that a single-site SERS observation could be used as a novel tool to find, develop, and implement applications of plasmon-induced photoexcitation of materials.