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arXiv · 1303.0277

Competition between extinction and enhancement in surface enhanced Raman spectroscopy

Thomas van Dijk·Sean T. Sivapalan·Brent M. DeVetter·Timothy K. Yang·Matthew V. Schulmerich·Catherine J. Murphy·Rohit Bhargava·P. Scott Carney
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Abstract

Conjugated metallic nanoparticles are a promising means to achieve ultrasensitive and multiplexed sensing in intact three-dimensional samples, especially for biological applications, via surface enhanced Raman scattering (SERS). We show that enhancement and extinction are linked and compete in a collection of metallic nanoparticles. Counterintuitively, the Raman signal vanishes when nanoparticles are excited at their plasmon resonance, while increasing nanoparticle concentrations at off-resonance excitation sometimes leads to decreased signal. We develop an effective medium theory that explains both phenomena. Optimal choices of excitation wavelength, individual particle enhancement factor and concentrations are indicated.

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Thomas van Dijk, Sean T. Sivapalan, Brent M. DeVetter, Timothy K. Yang, Matthew V. Schulmerich, Catherine J. Murphy, Rohit Bhargava, P. Scott Carney. 2013-03-01. Competition between extinction and enhancement in surface enhanced Raman spectroscopy. https://doi.org/10.1021/jz4005043

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