Rationale for $10^{14}$ enhancement factor in single molecule Raman spectroscopy
Autor: | Gaponenko, S. V., Guzatov, D. V. |
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Rok vydání: | 2008 |
Předmět: | |
Druh dokumentu: | Working Paper |
Popis: | 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 $10^{14}$-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. Comment: 5 pages, 2 figures |
Databáze: | arXiv |
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