Abstract

A strain measurement method based on nanophotonics is described. In this technique, a noble metal probe or nanoparticle film is used to enhance the probability of Raman scattering by using the surface plasmon resonance effect. An incident laser with a wavelength tuned to the surface plasmon resonance excites surface plasmons in a metal nanoparticle. As a result, the electromagnetic field near the probe is enhanced. The region in which Raman scattering is enhanced is in the nanoscale and the spatial resolution of the Raman microprobe is thereby extended. The method requires a scanning probe microscope to be coupled to a confocal Raman microscope and spectrometer. The development of high contrast tip enhanced Raman spectroscopy and tip preparation techniques are discussed.