Celiksoy Sirin, Ye Weixiang, Wandner Karl, Kaefer Katharina, Sönnichsen Carsten
Department of Chemistry, University of Mainz, Duesbergweg 10-14, D-55128 Mainz, Germany.
Nano Lett. 2021 Mar 10;21(5):2053-2058. doi: 10.1021/acs.nanolett.0c04702. Epub 2021 Feb 22.
Plasmon sensors respond to local changes of their surrounding environment with a shift in their resonance wavelength. This response is usually detected by measuring light scattering spectra to determine the resonance wavelength. However, single wavelength detection has become increasingly important because it simplifies the setup, increases speed, and improves statistics. Therefore, we investigated theoretically how the sensitivity toward such single wavelength scattering intensity changes depend on the material and shape of the plasmonic sensor. Surprisingly, simple equations describe this intensity sensitivity very accurately and allow us to distinguish the various contributions: Rayleigh scattering, dielectric contrast, plasmon shift, and frequency-dependent plasmon bulk damping. We find very good agreement of theoretical predictions and experimental data obtained by single particle spectroscopy.
表面等离子体传感器通过其共振波长的偏移来响应周围环境的局部变化。这种响应通常通过测量光散射光谱来检测，以确定共振波长。然而，单波长检测变得越来越重要，因为它简化了设置、提高了速度并改善了统计数据。因此，我们从理论上研究了对这种单波长散射强度变化的灵敏度如何取决于表面等离子体传感器的材料和形状。令人惊讶的是，简单的方程能够非常准确地描述这种强度灵敏度，并使我们能够区分各种贡献：瑞利散射、介电对比度、表面等离子体偏移和频率相关的表面等离子体体阻尼。我们发现理论预测与通过单粒子光谱获得的实验数据非常吻合。
