ABSTRACT
Metallic nanoparticles that can support plasmon resonances are called plasmonic nanoparticles and these are the important building blocks in nanoplasmonic applications. Their surface plasmon resonances (SPR)—collective free electron charge oscillations-provide tunable extinction in the visible to near-infrared range that are dependent on geometric size, shape, and environment. Owing to their highly sensitive resonances, many applications have been proposed, including biosensors [1-3], nanoantennas [4-7], and nonlinear biomarkers [8-11]. Further, their strong and weak SPR coupling property is proposed to be used as a “plasmonic ruler” for detecting DNA folding and unfolding [12] and nanometer-scale plasmonic circuit elements [13-15].
