Rationale for $10^{14}$ enhancement factor in single molecule Raman spectroscopy
Abstract
We extend the Purcell's original idea [Phys. Rev. \textbf{69}, 682 (1946)] on modification of photon spontaneous \textit{emission} rate to modification of photon spontaneous \textit{scattering} rate. We find the interplay of local incident field enhancement and local density of photon states enhancement in close proximity to a silver nanoparticle may result in up to -fold rise of Raman scattering cross-section. Thus single molecule Raman detection is found to be explained by consistent quantum electrodynamic description without any chemical mechanism involved. A model of the so-called "hot points" in surface enhanced spectroscopy has been elaborated as local areas with high Q-factor at incident and scattered (emitted) light frequencies. For verification of the model we consider further experiments including transient Raman experiments to clarify incident field enhancement and scanning near-field optical mapping of local density of photon states.
Cite
@article{arxiv.0811.1673,
title = {Rationale for $10^{14}$ enhancement factor in single molecule Raman spectroscopy},
author = {S. V. Gaponenko and D. V. Guzatov},
journal= {arXiv preprint arXiv:0811.1673},
year = {2008}
}
Comments
5 pages, 2 figures