Switching plasmon coupling through the formation of dimers from polyaniline-coated gold nanospheres.

摘要: Active modulation of the plasmon coupling in homodimers polyaniline (PANI)-coated Au nanospheres is achieved by changing proton-doping state PANI shell. Such a PANI-enabled dimers gives rise to remarkable spectral shifts, which show an exponential dependence on interparticle gap distance. For dimer with 10 nm shell thickness and 0.5 distance, shift stronger scattering peak response active reaches 231 nm. Electrodynamic simulations reveal that dipolar bonding mode dominates position variation for different distances. Moreover, quadrupolar can be turned off controlling distances less than ∼3 These results are high importance fundamentally understanding sensitivity coupled resonance modes dielectric environment, as well designing plasmonic devices performances.