Near-field enhanced Raman spectra by an apertureless probe: Observation of characteristic Stokes-shift peaks in near-field region

Abstract

A vibrational spectrum of a molecule is detectable with a resolution beyond a diffracted limitation of the wavelength by measuring Raman scattering from the molecule in the near-field region. In principle, it enables us to observe dynamics of a molecule with a spatial resolution of molecular scale. Realization of the near-field Raman spectroscopy requires achievement of spatially nanometric resolution and increment of cross section of Raman scattering of which value is typically 10^-30 cm². In this paper, we have reported the observation of the enhancement and shift of specific Stoke-shifted lines in near-field detection of the Raman scattering during scanning the probe on the sample.