Abstract

Tip-enhanced Raman spectroscopy (TERS) is a unique and indispensable imaging technique which enables analysis of nano-materials with a spatial resolution of a few tens of nanometers together with a strong enhancement of weak Raman signals from the nanometric volume of a sample [1]. The strong enhancement and photon localization is realized with plasmonic metallic tips [2]. While gold and silver, commonly used tip materials, are effective plasmonic metals in the visible wavelengths, in the deep UV (DUV) wavelength region, these metals behave absorptive dielectrics but not as metal. This has limited the use of TERS in the visible wavelengths. However, DUV is an interesting wavelength region in spectroscopy and microscopy because molecules such as nucleotides and proteins show characteristic resonance Raman scatterings, which can be effectively combined with plasmonic tip-enhancement.

© 2017 Japan Society of Applied Physics, Optical Society of America