6533b823fe1ef96bd127f65f
RESEARCH PRODUCT
Highly Sensitive plasmonic silver nanorods
Yuriy KhalavkaArpad JakabJan BeckerUlrich HohenesterAndreas TrüglerChristina RosmanCarsten Sönnichsensubject
Materials sciencebusiness.industryGeneral EngineeringAnalytical chemistryPhysics::OpticsGeneral Physics and AstronomyResonance02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesSilver nanoparticle0104 chemical sciencesWavelengthPhysics::Atomic and Molecular ClustersOptoelectronicsParticleGeneral Materials ScienceNanorodsense organsSurface plasmon resonance0210 nano-technologybusinessPlasmonLocalized surface plasmondescription
We compare the single-particle plasmonic sensitivity of silver and gold nanorods with similar resonance wavelengths by monitoring the plasmon resonance shift upon changing the environment from water to 12.5% sucrose solution. We find that silver nanoparticles have 1.2 to 2 times higher sensitivity than gold, in good agreement with simulations based on the boundary-elements-method (BEM). To exclude the effect of particle volume on sensitivity, we test gold rods with increasing particle width at a given resonance wavelength. Using the Drude-model of optical properties of metals together with the quasi-static approximation (QSA) for localized surface plasmons, we show that the dominant contribution to higher sensitivity of silver is the lower background polarizability of the d-band electrons and provide a simple formula for the sensitivity. We improve the reversibility of the silver nanorod sensors upon repeated cycles of environmental changes by blocking the high energy parts of the illumination light.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-08-20 | ACS Nano |