Optically-active hybrid nanostructures: Injection of hot plasmonic electrons, exciton-plasmon interaction, chirality and related applications

Summary form only given. Excitons and plasmons in nanocrystals strongly interact via Coulomb and electromagnetic fields and this interaction leads to characteristic interference effects which can be observed in optical spectra [1-6]. An interaction between a discrete state of exciton and a continuum of plasmonic states gives rise to Fano-like asymmetric resonances and anti-resonances [2,4]. These interference effects can strongly enhance visibility of relatively weak exciton signals and can be used for spectroscopy of single nanoparticles and molecules. If a system includes chiral elements (chiral molecules or nanocrystals), the exciton-plasmon interaction is able to alter and enhance circular dichroism (CD) of chiral components [5-8]. In particular, the exciton-plasmon interaction may create new chiral plasmonic lines in CD spectra of biomolecule-nanocrystal complexes [5,7]. Strong CD signals may also appear in purely plasmonic systems with a chiral geometry and a strong particle-particle interaction [6,8]. Recent experiments on molecule-nanocrystal and multi-nanocrystal complexes showed the appearance of strong plasmonic signals in CD spectra [7,8]. Potential applications of dynamic hybrid nanostructures include sensors and new optical and plasmonic materials.