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arXiv · 0806.2534

Nanostructure design for surface-enhanced Raman spectroscopy - prospects and limits

Sanshui Xiao·Niels Asger Mortensen·Antti-Pekka Jauho
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Abstract

Surface-enhanced Raman spectroscopy (SERS) allows single-molecule detection due to the strong field localization occurring at sharp bends or kinks of the metal-vacuum interface. An important question concerns the limits of the signal enhancement that can be achieved via a judicious design of the surface. By using a specific example of a technologically realizable nanopatterned surface, we demonstrate that while very high enhancement factors (~10^12) can be found for an ideal surface, these are unlikely to be achieved in laboratory samples, because even a minute, inevitable rounding-off strongly suppresses the enhancement, as well as shifts the optimal frequency. Our simulations indicate that the geometric enhancement factors are unlikely to exceed ~10^8 for real samples, and that it is necessary to consider the geometric uncertainty to reliably predict the frequency for maximum enhancement.

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Sanshui Xiao, Niels Asger Mortensen, Antti-Pekka Jauho. 2008-06-16. Nanostructure design for surface-enhanced Raman spectroscopy - prospects and limits. https://doi.org/10.2971/jeos.2008.08022

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