کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1810348 | 1025557 | 2012 | 5 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Collective resonances in plasmonic crystals: Size matters Collective resonances in plasmonic crystals: Size matters](/preview/png/1810348.png)
Periodic arrays of metallic nanoparticles may sustain surface lattice resonances (SLRs), which are collective resonances associated with the diffractive coupling of localized surface plasmons resonances (LSPRs). By investigating a series of arrays with varying number of particles, we traced the evolution of SLRs to its origins. Polarization resolved extinction spectra of arrays formed by a few nanoparticles were measured, and found to be in very good agreement with calculations based on a coupled dipole model. Finite size effects on the optical properties of the arrays are observed, and our results provide insight into the characteristic length scales for collective plasmonic effects: for arrays smaller than ∼5×5∼5×5 particles, the Q -factors of SLRs are lower than those of LSPRs; for arrays larger than ∼20×20∼20×20 particles, the Q-factors of SLRs saturate at a much larger value than those of LSPRs; in between, the Q-factors of SLRs are an increasing function of the number of particles in the array.
Journal: Physica B: Condensed Matter - Volume 407, Issue 20, 15 October 2012, Pages 4081–4085